Compositions in the form of dissolvable solid structures

ABSTRACT

Described are dissolvable, porous solid structures formed using certain vinyl acetate-vinyl alcohol copolymers. The copolymer and the porosity of the structure allow for liquid flow during use such that the structure readily dissolves to provide a desired consumer experience. Also described are processes for making open cell foam and fibrous dissolvable solid structures.

FIELD OF THE INVENTION

The present invention relates to compositions in the form of dissolvablesolid structures. The dissolvable solid structures are formed usingcertain polymers that allow the structures to perform well for theirintended use and allow for beneficial manufacturing conditions.

BACKGROUND OF THE INVENTION

Many personal care, fabric care and other consumer products in themarket today are sold in liquid form. While widely used, liquid productsoften have tradeoffs in terms of packaging, storage, transportation, andconvenience of use. Liquid consumer products typically are sold inbottles which add cost as well as packaging waste, much of which ends upin land-fills.

Dissolvable solid products have been disclosed, comprising awater-soluble polymeric structurant and a surfactant or otheringredients. Although existing dissolvable products provide goodperformance benefits to end users, the processes for making them canhave less than optimal cost, rate of manufacture, and/or productvariability parameters.

A need therefore still exists for dissolvable solid structures whichperform well for their intended purpose and can be manufactured withindesired cost and rate parameters. Additionally, it is desirable toimprove the dissolving properties of the solid product to facilitateimproved consumer satisfaction.

SUMMARY OF THE INVENTION

A Structure in the form of a porous dissolvable solid, comprising: (a)from about 1 wt % to about 95 wt % surfactant; and (b) from about 5 wt %to about 50 wt % of a vinyl acetate-vinyl alcohol copolymer, whereinsaid copolymer comprises not more than about 84% alcohol units.

A Structure in the form of a porous dissolvable solid that is an opencelled foam, comprising: (a) from about 1 wt % to about 75 wt %surfactant; and (b) from about 10 wt % to about 50 wt % of a vinylacetate-vinyl alcohol copolymer, wherein said copolymer comprises notmore than about 84% alcohol units; wherein the foam Structure has apercent open cell of from about 80% to about 100%.

A Structure in the form of a porous dissolvable solid comprising aplurality of fibers comprising: (1) from about 1 wt % to about 95 wt %surfactant; and (2) from about 5 wt % to about 50 wt % of a vinylacetate-vinyl alcohol copolymer, wherein said copolymer comprises notmore than about 84% alcohol units.

A process for preparing a Structure in the form of a porous dissolvablesolid that is an open celled foam, comprising the steps of: (a)preparing a pre-mixture comprising (1) from about 1 wt % to about 75 wt% surfactant, (2) from about 0.1 wt % to about 25 wt % of a vinylacetate-vinyl alcohol copolymer, (3) not more than about 60 wt % water,and (4) optionally from about 0.1 wt % to about 25 plasticizer; whereinthe pre-mixture: (i) has a viscosity at 70° C. of from about 1000 cps toabout 100,000 cps and (ii) is heated to a temperature in the range offrom about 60° C. to about 100° C.; (2) aerating the pre-mixture byintroducing a gas into the pre-mixture to form a wet aerated mixture,wherein said wet aerated mixture comprises: (i) a density of from about0.15 to about 0.65 g/ml and (ii) bubbles having a diameter of from about5 to about 100 microns; (3) dosing the wet aerated mixture intoindividual cavities in a mold or as a continuous sheet; and (4) dryingthe wet aerated mixture by applying energy to heat the wet aeratedmixture and evaporate water to provide a Structure; wherein theStructure has a percent open cell of from about 70% to about 100%.

A process for preparing a Structure in the form of a porous dissolvablesolid comprising a significant number of fibers, comprising the stepsof: (a) preparing a processing mixture comprising one or more vinylacetate-vinyl-alcohol copolymers; one or more surfactants; and not morethan about 60 wt % water; wherein the processing mixture has: aviscosity at 70° C. of from about 5,000 centipoise to about 150,000centipoise; (b) fibrillating the processing mixture into fibers by afluid film fibrillation process comprising a first pressurized gasstream directed against a liquid film of the processing mixture to formthe fibers; (c) at least partially drying the fibers of the processingmixture by a second pressurized gas stream; (d) depositing the partiallydry fibers on a surface to form a web of partially dry fibrous webstructures; and (e) drying the partially dry fibrous web structure to adesired final moisture content.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic representation of an apparatus suitable for makingfibers according to the present invention.

FIG. 2 is a schematic representation of a die suitable for spinningfibers according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION Definitions

As used herein, the “average diameter” of the fibers making up aStructure is calculated as an arithmetic mean of diameters of all thedissolvable fibers in the sample measured. The relative standarddeviation of fiber diameter is calculated by dividing the statisticalstandard deviation of the diameter by the average diameter of all thefibers in the measured sample. The method of measuring fiber diameter isdescribed later in the disclosure.

As used herein, “dissolvable” means that the Structure meets the handdissolution values discussed herein. The Structure has a handdissolution value of from about 1 to about 30 strokes, in one embodimentfrom about 2 to about 25 strokes, in another embodiment from about 3 toabout 20 strokes, and in still another embodiment from about 4 to about15 strokes, as measured by the Hand Dissolution Method.

As used herein, “flexible” means a Structure meets the distance tomaximum force values discussed herein.

As used herein “open celled foam” means a solid, interconnected,polymer-containing matrix that defines a network of spaces or cells thatcontain a gas, typically a gas such as air, without collapse of the foamstructure during the drying process, thereby maintaining the physicalstrength and cohesiveness of the solid. The interconnectivity of thestructure may be described by a Star Volume, a Structure Model Index(SMI) and a Percent Open Cell Content.

As used herein, “porous” means that the Structure has spaces, voids orinterstices, (generally referred to herein as “pores”) provided by themicroscopic complex three-dimensional configuration, that providechannels, paths or passages through which a liquid can flow.

As used herein, “porosity” and “percent porosity” are usedinterchangeably and each refers to a measure of void volume of theStructure and is calculated as

[1−([basis weight of Structure]/[thickness of Structure×density of thebulk, dried material])]×100%

with the units adjusted so they cancel and multiplied by 100% to providepercent porosity.

The structure may be referred to herein as “the Structure” or “theDissolvable Structure”.

As used herein, “vinyl acetate-vinyl alcohol copolymer” (and “copolymer”when used in reference thereto) refers to a polymer of the followingstructure (I):

In structure (I), m and n are integers such that the copolymer has thedegree of polymerization and percent alcohol characteristics describedherein. For purposes of clarity, this use of the term “copolymer” isintended to convey that the partially hydrolyzed polyvinyl acetate ofthe present invention comprises vinyl alcohol and vinyl acetate units.As discussed below, the copolymer is routinely prepared by polymerizingvinyl acetate monomer followed by hydrolysis of some of the acetategroups to alcohol groups, as opposed to polymerization of vinyl acetateand vinyl alcohol monomer units (due in-part to the instability of vinylalcohol).

As used herein, the articles including “a” and “an” when used in aclaim, are understood to mean one or more of what is claimed ordescribed.

As used herein, the terms “include,” “includes,” and “including,” aremeant to be non-limiting.

The methods disclosed in the Test Methods Section of the presentapplication should be used to determine the respective values of theparameters of Applicants' inventions, including those discussed in theDissolvable Structures—Physical Characteristics section below.

All percentages and ratios are calculated by weight unless otherwiseindicated. All percentages and ratios are calculated based on the totalcomposition unless otherwise indicated.

It should be understood that every maximum numerical limitation giventhroughout this specification includes every lower numerical limitation,as if such lower numerical limitations were expressly written herein.Every minimum numerical limitation given throughout this specificationwill include every higher numerical limitation, as if such highernumerical limitations were expressly written herein. Every numericalrange given throughout this specification will include every narrowernumerical range that falls within such broader numerical range, as ifsuch narrower numerical ranges were all expressly written herein.

I. DISSOLVABLE STRUCTURES—PHYSICAL CHARACTERISTICS

The Structures of the present invention are in the form of adissolvable, porous solid composition wherein the porosity allows forliquid (e.g., water) flow during use such that the solid compositionreadily dissolves to provide a desired consumer experience. The porousnature of the Structure can be achieved in a variety of ways including,for example, forming an open celled foam or forming a fibrous structure.

In one embodiment, the percent porosity of the dissolvable solidStructure is at least about 25%, in another embodiment at least about50%, in another embodiment at least about 60%, in another embodiment atleast about 70% and in another embodiment at least about 80%. In oneembodiment, the porosity of the dissolvable solid Structure is not morethan about 99%, in another embodiment not more than about 98%, inanother one embodiment not more than about 95%, and in anotherembodiment not more than about 90%. Porosity of a Structure isdetermined according to the procedure set forth in the definition of“porosity” above.

A range of effective sizes of pores can be accommodated. The pore sizedistribution through the Structure cross-section may be symmetric orasymmetric.

In one embodiment, the Structure will be flexible and have a distance tomaximum force value of from about 6 mm to about 30 mm. In anotherembodiment the distance to maximum force value from about 7 mm to about25 mm, in another embodiment from about 8 mm to about 20 mm, and instill another embodiment from about 9 mm to about 15 mm.

The Structure can be characterized in one aspect by its Specific SurfaceArea. In one embodiment, the Structure has a Specific Surface Area offrom about 0.03 m²/g to about 0.25 m²/g, in another embodiment fromabout 0.035 m²/g to about 0.22 m²/g, in another embodiment from about0.04 m²/g to about 0.19 m²/g, and in still another embodiment from about0.045 m²/g to about 0.16 m²/g.

In one embodiment the Structure is a flat, flexible substrate in theform of a pad, a strip, or tape and having a thickness of from about 0.5mm to about 10 mm, in one embodiment from about 1 mm to about 9 mm, inanother embodiment from about 2 mm to about 8 mm, and in a furtherembodiment from about 3 mm to about 7 mm as measured by the belowmethodology. In another embodiment, the Structure is a sheet having athickness from about 5 mm to about 6.5 mm. In another embodiment, two ormore sheets are combined to form a Structure with a thickness of about 5mm to about 10 mm.

In one embodiment, the Structure has a basis weight of from about 200grams/m² to about 2,000 grams/m², in another embodiment from about 400g/m² to about 1,200 g/m², in another embodiment from about 600 g/m² toabout 2,000 g/m², and in still another embodiment from about 700 g/m² toabout 1,500 g/m².

In one embodiment, the Structure has a dry density of from about 0.08g/cm³ to about 0.30 g/cm³, in another embodiment from about 0.10 g/cm³to about 0.25 g/cm³, and in another embodiment from about 0.12 g/cm³ toabout 0.20 g/cm³.

For open cell foam Structures, the Structure has a Cell Wall Thickness.The Structure in one embodiment has a Cell Wall Thickness of from about15 microns to about 55 microns, in another embodiment from about 20microns to about 45 microns, and in another embodiment from about 25microns to about 35 microns.

For open cell foam Structures, in one embodiment the Structure has aStar Volume of from about 1 mm³ to about 90 mm³, in another embodimentfrom about 5 mm³ to about 80 mm³, in another embodiment from about 10mm³ to about 70 mm³, and in still another embodiment from about 15 mm³to about 60 mm³. In one embodiment, the open cell foam Structure has anon-negative Structure Model Index of from about 0.0 to about 3.0, inone embodiment from about 0.5 to about 2.75, and in another embodimentfrom about 1.0 to about 2.50.

For open cell foam Structures, in one embodiment the Structure has aPercent Open Cell Content of from about 70% to 100%, in one embodimentfrom about 80% to about 97.5%, and in another embodiment from about 90%to about 95%.

For fibrous Structures, in one embodiment the Structure comprises asignificant number of dissolvable fibers with an average diameter lessthan about 150 micron, in another embodiment less than about 100 micron,in an another embodiment less than about 10 micron, and in an yetanother embodiment less than about 1 micron with a relative standarddeviation of less than 100%, alternatively less than 80%, alternativelyless than 60%, alternatively less than 50%, such as in the range of 10%to 50%, for example. As set forth herein, the significant number meansat least 10% of all the dissolvable fibers, in another embodiment atleast 25% of all the dissolvable fibers, in another embodiment at least50% of all the dissolvable fibers, in yet another embodiment at least75% of all the dissolvable fibers. In a particular embodiment, thesignificant number may be at least 99% of all the dissolvable fibers. Ina further embodiment, at least 50% of all the dissolvable fibers mayhave an average diameter less than about 10 micron. The dissolvablefibers produced by the method of the present disclosure have asignificant number of dissolvable fibers with an average diameter lessthan about 1 micron, or sub-micron fibers. In an embodiment, the articlecomprising Structure may have at least 25% of all the dissolvable fiberswith an average diameter less than about 1 micron, in another embodimentat least 35% of all the dissolvable fibers with an average diameter lessthan about 1 micron, in another embodiment at least 50% of all thedissolvable fibers with an average diameter less than about 1 micron,and in yet another embodiment at least 75% of all the dissolvable fiberswith an average diameter less than about 1 micron.

II. DISSOLVABLE STRUCTURES—COMPOSITIONAL

The Structure (dried) of the present invention is in the form of aporous dissolvable solid, comprising: (a) from about 1 wt % to about 95wt % surfactant; and (b) from about 5 wt % to about 50 wt % of a vinylacetate-vinyl alcohol copolymer, wherein said copolymer comprises notmore than about 84% alcohol units. In one embodiment, the Structurecomprises from about 3 wt % to about 75 wt % surfactant; and in anotherembodiment from about 5 wt % to about 65 wt % surfactant. In oneembodiment, the Structure comprises from about 10 wt % to about 50 wt %of the copolymer, in another embodiment from about 15 wt % to about 40wt % of the copolymer, and in another embodiment from about 20 wt % toabout 30 wt % of the copolymer.

A. Copolymer

The Structures of the present invention comprise at least one copolymercomprising vinyl acetate and vinyl alcohol units, wherein the copolymercomprises not more than about 84% alcohol units. While copolymerscomprised of vinyl acetate and vinyl alcohol units have been used in thepast to make good performing dissolvable structures (e.g., U.S. Pat.Nos. 8,466,099 and 8,461,090), the copolymers identified had a higherdegree of vinyl alcohol content (i.e., higher degree of hydrolysis ofthe polyvinyl acetate starting polymer)—typically around 88%—than thecopolymers used herein. Applicants have discovered that while the use ofhigher vinyl alcohol content copolymers are quite acceptable, there aresurprising benefits associated with the lower alcohol content copolymersdescribed herein. One important benefit is the lower alcohol copolymersallow for the use of significantly less water during production of theporous Structure. Among other things, this allows faster productionrates resulting from less water introduction at the front end of theprocess and reduced drying time and energy after Structure formation.These benefits are reflected in the Examples section below.

In one embodiment, the copolymer comprises not more than about 82.5%alcohol units and in another embodiment not more than about 81% alcoholunits. In one embodiment, the copolymer comprises from about 65% toabout 84% alcohol units, in another embodiment from about 65% to about82.5% alcohol units, and still another embodiment from about 70% toabout 81% alcohol units. The percentage of alcohol units (i.e., thedegree of hydrolysis) can be determined using standard titrationchemistry techniques. One such procedure is described in ISO15023-2:2003.

The degree of polymerization (average molecular weight) of the vinylacetate-vinyl alcohol copolymer is measured using gel permeationchromatography (GPC). This form of chromatography utilizes sizeexclusion. Separation occurs through a column packed with porous beads.Smaller analytes spend more time in the pores and thus pass through thecolumn more slowly. A detector measures the amount of polymer in theelution solvent as it is eluted. Reference herein to the molecularweight of the copolymer is weight average molecular weight (“Mw”). TheMw of the copolymer can vary widely, but in one embodiment the copolymerwill have a Mw of from about 20,000 to about 500,000, in one embodimentfrom about 40,000 to about 400,000, in yet another embodiment from about60,000 to about 300,000, and in still another embodiment from about70,000 to about 200,000.

In one embodiment, the porous dissolvable Structures can be prepared bycombining two or more vinyl acetate-vinyl alcohol copolymer materialsdescribed herein, wherein the copolymer materials differ with respect toeither or both their degree of polymerization and/or their degree ofhydrolysis.

The benefits identified can be achieved by using one copolymer describedabove, or it is possible to use two distinct vinyl acetate-vinyl alcoholcopolymers.

In one embodiment, the porous dissolvable solid Structures can beprepared by combining a vinyl acetate-vinyl alcohol copolymer describedherein with a polyvinylalcohol/polyvinylacetate having a higher degreeof hydrolysis (e.g., about 88% hydrolyzed; “high hydrolysispolyvinylalcohol”). In such cases, the ratio (weight:weight) of thevinyl acetate-vinyl alcohol copolymer to high hydrolysispolyvinylalcohol will typically be from about 5:1 to about 1:5.

The vinyl acetate-vinyl alcohol copolymer useful in the presentinvention is readily prepared using well known chemistry. One suchmethod is the hydrolysis of a starting polyvinyl ester (polyvinylacetate; formed via polymerization of vinyl acetate monomer units) ofthe desired degree of polymerization with absolute alcohols (e.g.,methanol) in the presence of catalytic amounts of alkali (e.g., sodiummethoxide). In the hydrolysis of polyvinyl acetate to vinylacetate-vinyl alcohol copolymer, products with different alcohol groupcontents can be obtained depending on production conditions. Hydrolysisconditions influence the structure of the vinyl acetate-vinyl alcoholcopolymer formed. By varying catalyst concentration, reactiontemperature, and the reaction time, the content of residual acetylgroups (i.e., unhydrolyzed acetyl groups) can be adjusted routinely.See, for example, Polyvinyl Compounds, Others, Ullmann's Encyclopedia ofIndustrial Chemistry, Vol. 29, p. 605-609 (2000). Vinyl acetate-vinylalcohol copolymers are also available commercially, e.g. from KurarayEurope GmbH.

B. Surfactants

The Structure comprises one or more surfactants suitable for applicationto the hair or skin. Surfactants suitable for use in the Structureinclude anionic surfactants, nonionic surfactants, cationic surfactants,zwitterionic surfactants, amphoteric surfactants, polymeric surfactantsor combinations thereof. Although representative surfactants aredescribed herein, the skilled artisan will recognize that othersurfactants can be readily substituted and similar benefits can bederived from use of the vinyl acetate-vinyl alcohol copolymers describedherein. Each patent described throughout this application isincorporated herein by reference to the extent each provides guidanceregarding surfactants suitable for inclusion in the Structure.

In one embodiment, the Structure is a lathering dissolvable solidpersonal care product (dried) and comprises from about 23 wt % to about75 wt % surfactant, in one embodiment from about 30 wt % to about 70 wt% surfactant, in another embodiment from about 40 wt % to about 65 wt %surfactant.

Suitable anionic surfactants include alkyl and alkyl ether sulfates.Other suitable anionic surfactants are the water-soluble salts oforganic, sulfuric acid reaction products. Still other suitable anionicsurfactants are the reaction products of fatty acids esterified withisethionic acid and neutralized with sodium hydroxide. Other similaranionic surfactants are described in U.S. Pat. Nos. 2,486,921;2,486,922; and 2,396,278, which are incorporated herein by reference intheir entirety.

Exemplary anionic surfactants include ammonium lauryl sulfate, ammoniumlaureth sulfate, triethylamine lauryl sulfate, triethylamine laurethsulfate, triethanolamine lauryl sulfate, triethanolamine laurethsulfate, monoethanolamine lauryl sulfate, monoethanolamine laurethsulfate, diethanolamine lauryl sulfate, diethanolamine laureth sulfate,lauric monoglyceride sodium sulfate, sodium lauryl sulfate, sodiumlaureth sulfate, potassium lauryl sulfate, potassium laureth sulfate,sodium lauryl sarcosinate, sodium lauroyl sarcosinate, lauryl sarcosine,cocoyl sarcosine, ammonium cocoyl sulfate, ammonium lauroyl sulfate,sodium cocoyl sulfate, sodium lauroyl sulfate, potassium cocoyl sulfate,potassium lauryl sulfate, triethanolamine lauryl sulfate,triethanolamine lauryl sulfate, monoethanolamine cocoyl sulfate,monoethanolamine lauryl sulfate, sodium tridecyl benzene sulfonate,sodium dodecyl benzene sulfonate, sodium cocoyl isethionate andcombinations thereof. In one embodiment, the anionic surfactant issodium lauryl sulfate or sodium laureth sulfate.

In one embodiment, the anionic surfactant is at least one branchedsulfate having the formulaCH₃—(CH₂)_(z)—CH(R¹)—CH₂—O—(CH₂CH(R²)O)_(y)—SO₃M; where z is from about3 to about 14; R¹ represents H or a hydrocarbon radical comprising 1 to4 carbon atoms, R² is H or CH3; R¹ and R² are not both H; y is 0 toabout 7; the average value of y is about 1 when y is not =0; and M is amono-valent or di-valent, positively-charged cation. Examples ofmono-valent positively charged cations include ammonium, sodium,potassium, triethanolamine cation, and examples of di-valent positivelycharged cations include magnesium. For the foregoing branched sulfates,“average value” means that whereas the composition may comprisemolecules having a value of y of other than 1, the average value of yall molecules in the composition is about 1.

Suitable amphoteric or zwitterionic surfactants include those which areknown for use in shampoo or other cleansing products. Non limitingexamples of suitable zwitterionic or amphoteric surfactants aredescribed in U.S. Pat. Nos. 5,104,646 and 5,106,609, which areincorporated herein by reference in their entirety.

Suitable amphoteric surfactants include those surfactants broadlydescribed as derivatives of aliphatic secondary and tertiary amines inwhich the aliphatic radical can be straight or branched chain andwherein one of the aliphatic substituents contains from about 8 to about18 carbon atoms and one contains an anionic group such as carboxy,sulfonate, sulfate, phosphate, or phosphonate. Exemplary amphotericdetersive surfactants include cocoamphoacetate, cocoamphodiacetate,lauroamphoacetate, lauroamphodiacetate, and mixtures thereof.

Suitable zwitterionic surfactants include those surfactants broadlydescribed as derivatives of aliphatic quaternaryammonium, phosphonium,and sulfonium compounds, in which the aliphatic radicals can be straightor branched chain, and wherein one of the aliphatic substituentscontains from about 8 to about 18 carbon atoms and one contains ananionic group such as carboxy, sulfonate, sulfate, phosphate orphosphonate. In another embodiment, zwitterionics such as betaines areselected.

Non limiting examples of other anionic, zwitterionic, amphoteric oroptional additional surfactants suitable for use in the compositions aredescribed in McCutcheon's, Emulsifiers and Detergents, 1989 Annual,published by M. C. Publishing Co., and U.S. Pat. Nos. 3,929,678,2,658,072; 2,438,091; 2,528,378, which are incorporated herein byreference in their entirety.

In another embodiment, the Structure is a substantially non-latheringdissolvable solid personal care product and comprises a) from about 0 wt% to about 10 wt % of an ionic (anionic, zwitterionic, cationic andmixtures thereof) surfactant, in one embodiment from about 0 wt % toabout 5 wt % of an ionic surfactant, and in another embodiment fromabout 0 wt % to about 2.5 wt % anionic surfactant, and b) from about 1wt % to about 50 wt % of a nonionic or polymeric surfactant, in oneembodiment from about 5 wt % to about 45 wt % of a nonionic or polymericsurfactant, and in another embodiment from about 10 wt % to about 40 wt% of a nonionic or polymeric surfactant, and combinations thereof.

Suitable nonionic surfactants for use in the present invention includethose described in McCutcheon's Detergents and Emulsifiers, NorthAmerican edition (2010), Allured Publishing Corp., and McCutcheon'sFunctional Materials, North American edition (2010). Suitable nonionicsurfactants for use in the Structure of the present invention include,but are not limited to, polyoxyethylenated alkyl phenols,polyoxyethylenated alcohols, polyoxyethylenated polyoxypropyleneglycols, glyceryl esters of alkanoic acids, polyglyceryl esters ofalkanoic acids, propylene glycol esters of alkanoic acids, sorbitolesters of alkanoic acids, polyoxyethylenated sorbitor esters of alkanoicacids, polyoxyethylene glycol esters of alkanoic acids,polyoxyethylenated alkanoic acids, alkanolamides, N-alkylpyrrolidones,alkyl glycosides, alkyl polyglucosides, alkylamine oxides, andpolyoxyethylenated silicones.

In another embodiment, the nonionic surfactant is selected from sorbitanesters and alkoxylated derivatives of sorbitan esters including sorbitanmonolaurate (SPAN® 20), sorbitan monopalmitate (SPAN® 40), sorbitanmonostearate (SPAN® 60), sorbitan tristearate (SPAN® 65), sorbitanmonooleate (SPAN® 80), sorbitan trioleate (SPAN® 85), sorbitanisostearate, polyoxyethylene (20) sorbitan monolaurate (Tween® 20),polyoxyethylene (20) sorbitan monopalmitate (Tween® 40), polyoxyethylene(20) sorbitan monostearate (Tween® 60), polyoxyethylene (20) sorbitanmonooleate (Tween® 80), polyoxyethylene (4) sorbitan monolaurate (Tween®21), polyoxyethylene (4) sorbitan monostearate (Tween® 61),polyoxyethylene (5) sorbitan monooleate (Tween® 81), all available fromUniqema, and combinations thereof.

Suitable polymeric surfactants include, but are not limited to, blockcopolymers of ethylene oxide and fatty alkyl residues, block copolymersof ethylene oxide and propylene oxide, hydrophobically modifiedpolyacrylates, hydrophobically modified celluloses, silicone polyethers,silicone copolyol esters, diquaternary polydimethylsiloxanes, andco-modified amino/polyether silicones.

C. Optional Ingredients

The Structure (dried) optionally comprises from about 1 wt % to about 25wt % plasticizer, in one embodiment from about 3 wt % to about 20 wt %plasticizer, in one embodiment from about 5 wt % to about 15 wt %plasticizer.

When present in the Structures, non-limiting examples of suitableplasticizing agents include polyols, copolyols, polycarboxylic acids,polyesters and dimethicone copolyols.

Examples of useful polyols include, but are not limited to, glycerin,diglycerin, propylene glycol, ethylene glycol, butylene glycol,pentylene glycol, cyclohexane dimethanol, hexane diol, polyethyleneglycol (200-600), sugar alcohols such as sorbitol, manitol, lactitol andother mono- and polyhydric low molecular weight alcohols (e.g., C₂-C₈alcohols); mono di- and oligo-saccharides such as fructose, glucose,sucrose, maltose, lactose, and high fructose corn syrup solids andascorbic acid.

Examples of polycarboxylic acids include, but are not limited to citricacid, maleic acid, succinic acid, polyacrylic acid, and polymaleic acid.

Examples of suitable polyesters include, but are not limited to,glycerol triacetate, acetylated-monoglyceride, diethyl phthalate,triethyl citrate, tributyl citrate, acetyl triethyl citrate, acetyltributyl citrate.

Examples of suitable dimethicone copolyols include, but are not limitedto, PEG-12 dimethicone, PEG/PPG-18/18 dimethicone, and PPG-12dimethicone.

Other suitable plasticizers include, but are not limited to, alkyl andallyl phthalates; napthalates; lactates (e.g., sodium, ammonium andpotassium salts); sorbeth-30; urea; lactic acid; sodium pyrrolidonecarboxylic acid (PCA); sodium hyraluronate or hyaluronic acid; solublecollagen; modified protein; monosodium L-glutamate; alpha & betahydroxyl acids such as glycolic acid, lactic acid, citric acid, maleicacid and salicylic acid; glyceryl polymethacrylate; polymericplasticizers such as polyquaterniums; proteins and amino acids such asglutamic acid, aspartic acid, and lysine; hydrogen starch hydrolysates;other low molecular weight esters (e.g., esters of C₂-C₁₀ alcohols andacids); and any other water soluble plasticizer known to one skilled inthe art of the foods and plastics industries; and mixtures thereof.

EP 0283165 B1 discloses suitable plasticizers, including glycerolderivatives such as propoxylated glycerol.

The Structure may comprise other optional ingredients that are known foruse or otherwise useful in compositions, provided that such optionalmaterials are compatible with the selected essential materials describedherein, or do not otherwise unduly impair product performance.

Such optional ingredients are most typically those materials approvedfor use in cosmetics and that are described in reference books such asthe CTFA Cosmetic Ingredient Handbook, Second Edition, The Cosmetic,Toiletries, and Fragrance Association, Inc. 1992.

Emulsifiers suitable as an optional ingredient herein include mono- anddi-glycerides, fatty alcohols, polyglycerol esters, propylene glycolesters, sorbitan esters and other emulsifiers known or otherwisecommonly used to stabilized air interfaces, as for example those usedduring preparation of aerated foodstuffs such as cakes and other bakedgoods and confectionary products, or the stabilization of cosmetics suchas hair mousses.

Further non-limiting examples of such optional ingredients includepreservatives, perfumes or fragrances, coloring agents or dyes,conditioning agents, hair bleaching agents, thickeners, moisturizers,emollients, pharmaceutical actives, vitamins or nutrients, sunscreens,deodorants, sensates, plant extracts, nutrients, astringents, cosmeticparticles, absorbent particles, adhesive particles, hair fixatives,fibers, reactive agents, skin lightening agents, skin tanning agents,anti-dandruff agents, perfumes, exfoliating agents, acids, bases,humectants, enzymes, suspending agents, pH modifiers, hair colorants,hair perming agents, pigment particles, anti-acne agents, anti-microbialagents, sunscreens, tanning agents, exfoliation particles, hair growthor restorer agents, insect repellents, shaving lotion agents,co-solvents or other additional solvents, and similar other materials.

Suitable conditioning agents include high melting point fatty compounds,silicone conditioning agents and cationic conditioning polymers.Suitable materials are discussed in US 2008/0019935, US 2008/0242584 andUS 2006/0217288.

Non-limiting examples of product type embodiments for use by theStructure include hand cleansing substrates, hair shampoo or other hairtreatment substrates, body cleansing substrates, shaving preparationsubstrates, fabric care substrate (softening), dish cleaning substrates,pet care substrates, personal care substrates containing pharmaceuticalor other skin care active, moisturizing substrates, sunscreensubstrates, chronic skin benefit agent substrates (e.g.,vitamin-containing substrates, alpha-hydroxy acid-containing substrates,etc.), deodorizing substrates, fragrance-containing substrates, and soforth.

III. METHODS OF MANUFACTURE—OPEN CELL FOAMS

The use of low hydrolysis vinyl acetate-vinyl alcohol copolymersurprisingly allows for reduced water usage during Structure processing(when appropriately accounting for water introduced as the solvent forother materials). That is, the use of vinyl acetate-vinyl alcoholcopolymer allows for processing starting with a higher % solids contentpre-mixture. The % solids content is the summation of the weightpercentages by weight of the total processing mixture of all of thesolid, semi-solid and liquid components, excluding water and anyobviously volatile materials such as low boiling alcohols. Applicantshave also discovered that when making foam Structures using the vinylacetate-vinyl alcohol copolymer in a relatively low water (not more thanabout 60 wt %) or high % solids (about 40% or greater) process, thedried foams exhibit improved integrity compared to foams made using highhydrolysis polymers. This provides in-use benefits including improveddissolution, as reflected in the examples section below.

A process for preparing a dissolvable open celled foam Structurecomprising the steps of:

-   -   (a) preparing a pre-mixture comprising (1) from about 1 wt % to        about 75 wt % surfactant, (2) from about 0.1 wt % to about 25 wt        % of a vinyl acetate-vinyl alcohol copolymer, (3) not more than        about 60 wt % water, and (4) optionally from about 0.1 wt % to        about 25 plasticizer;        -   wherein the pre-mixture:        -   (i) has a viscosity at 70° C. of from about 1000 cps to            about 100,000 cps; and        -   (ii) is heated to a temperature in the range of from about            60° C. to about 100° C.;    -   (b) aerating the pre-mixture by introducing a gas into the        pre-mixture to form a wet aerated mixture, wherein said wet        aerated mixture comprises:        -   (i) a density of from about 0.15 to about 0.65 g/ml; and        -   (ii) bubbles having a diameter of from about 5 to about 100            microns;    -   (c) dosing the wet aerated mixture into individual cavities in a        mold or as a continuous sheet; and    -   (d) drying the wet aerated mixture by applying energy to heat        the wet aerated mixture and evaporate water to provide a        Structure;

wherein the Structure has a percent open cell of from about 70% to about100%.

In one embodiment, the pre-mixture comprises from about 0.1 wt % toabout 25 wt % of the pre-mixture of vinyl acetate-vinyl alcoholcopolymer, in one embodiment from about 5 wt % to about 15 wt %copolymer, in one embodiment from about 7 wt % to about 10 wt % of thepre-mixture of the copolymer.

In one embodiment, the pre-mixture comprises from about 0.1 wt % toabout 25 wt % of plasticizer, in one embodiment from about 1 wt % to 15wt % plasticizer, in one embodiment from about 2 wt % to about 10 wt %plasticizer, and in another embodiment from about 2 wt % to about 4 wt %plasticizer.

A. Preparation of Pre-Mixture

The pre-mixture is generally prepared by mixing the solids of interest,including surfactant(s), vinyl acetate-vinyl alcohol copolymer, optionalplasticizer and other optional ingredients. A benefit associated withuse of the vinyl acetate-vinyl alcohol copolymer is that for open cellfoam production, a relatively high solids content pre-mixture can beused. As discussed, high solids (i.e., reduced water) is of significantvalue as it allows for reduced water content on the front end of themaking process and, accordingly, reduced time and energy is required toremove water to arrive at the desired dry Structure.

In one embodiment, the pre-mixture can be formed using a mechanicalmixer. Mechanical mixers useful herein, include, but aren't limited topitched blade turbines or MAXBLEND mixer (Sumitomo Heavy Industries).

For addition of the ingredients in the pre-mixture, it can be envisionedthat the vinyl acetate-vinyl alcohol copolymer is ultimately dissolvedin the presence of water, the surfactant(s), optional actives,plasticizer, and any other optional ingredients including step-wiseprocessing via pre-mix portions of any combination of ingredients.

The pre-mixtures of the present invention comprise: at least about 40%solids, in one embodiment at least about 42%, in one embodiment at leastabout 44%, in another embodiment at least about 46%, and in anotherembodiment at least about 50%, by weight of the pre-mixture beforedrying.

In one embodiment, the viscosity of the pre-mixture is determined whenthe pre-mixture is heated to a temperature in the range of from about60° C. to about 99° C. In one embodiment, the viscosity is measured at 1sec⁻¹ and 70° C. In another embodiment, the viscosity of the pre-mixtureis measured at ambient temperatures (25° C.).

When the pre-mixture is heated to a temperature in the range of between60° C. and 99° C., it will have a viscosity of from about 1000 cps toabout 20,000 cps, in one embodiment from about 2,000 cps to about15,000cps, in one embodiment from about 3,000 cps to about 10,000 cps,and in another embodiment from about 4,000 cps to about 7,500 cps. Thepre-mixture viscosity values are measured using a Brookfield RVDV-1Prime Viscometer with CPE-41 cone and a shear rate of 1.0 reciprocalseconds for a period of 300 seconds.

B. Optional Continued Heating of Pre-Mixture

Optionally, the pre-mixture can be pre-heated immediately prior to theaeration process at above ambient temperature but below any temperaturesthat would cause degradation of the components. In one embodiment, thepre-mixture is kept at above about 40° C. and below about 99° C., inanother embodiment above about 50° C. and below about 95° C., in anotherembodiment from about 60° C. and below about 90° C. In one embodiment,when the pre-mixture is heated to a temperature in the range of between60° C. and 99° C., the pre-mixtures of the present invention have aviscosity of from about 1000 cps to about 20,000 cps, in one embodimentfrom about 2,000 cps to about 15,000cps, in one embodiment from about3,000 cps to about 10,000 cps, and in another embodiment from about4,000 cps to about 7,500 cps. In an additional embodiment, additionalheat is applied during the aeration process to try and maintain anelevated temperature during the aeration. This can be accomplished viaconductive heating from one or more surfaces, injection of steam orother processing means.

It is believed that the act of pre-heating the pre-mixture before theaeration step may provide a means for lowering the viscosity ofpre-mixtures comprising higher percent solids content for improvedintroduction of bubbles into the mixture and formation of the desiredStructure. Achieving higher percent solids content is desirable so as toreduce the energy requirements for drying. The increase of percentsolids, and therefore conversely the decrease in water level content,and increase in viscosity is believed to affect the film drainage withinthe pre-mixture during the drying step. This film drainage andevaporation of water from the pre-mixture during drying is believed toassist the formation of the open celled structure of the Structure.

Pre-heating of the pre-mixture also allows for the manufacture of a fastdissolving Structure even when using a more viscous processing mixture.Without pre-heating, these viscous processing mixtures with higherpercent solid levels normally produce Structures that are slowdissolving and that have predominately closed celled foams. However, theincreased temperature during pre-heating causes drainage from the thinliquid film separating the bubbles outwards into the plateau borders ofthe open celled foam. This drainage generates openings between thebubbles which become the open cells of the Structure. The demonstratedability to achieve such inter-connected open-celled foams of theStructures of the present invention is surprising.

In addition, a more viscous processing mixture results in Structureswith low percent (%) shrinkage after the drying process while stillmaintaining fast dissolution rates. This is due to the fact that duringthe drying process, pre-mixtures with higher viscosities are able tomitigate the drainage and bubble rupture/collapse/coalescence that giverise to the shrinkage.

C. Aeration of Pre-Mixture

The aeration of the pre-mixture to form the wet aerated mixture isaccomplished by introducing a gas into the pre-mixture in one embodimentby mechanical mixing energy, but also may be achieved via chemical meansto form an aerated mixture. The aeration may be accomplished by anysuitable mechanical processing means, including but not limited to: (i)batch tank aeration via mechanical mixing including planetary mixers orother suitable mixing vessels, (ii) semi-continuous or continuousaerators utilized in the food industry (pressurized andnon-pressurized), or (iii) spray-drying the processing mixture in orderto form aerated beads or particles that can be compressed such as in amold with heat in order to form the porous solid.

In another embodiment, aeration with chemical foaming agents by in-situgas formation (via chemical reaction of one or more ingredients,including formation of carbon dioxide (CO₂ (g)) by an effervescentsystem) can be used.

In a particular embodiment, it has been discovered that the Structurecan be prepared within continuous pressurized aerators that areconventionally utilized in the foods industry in the production ofmarshmallows. Suitable continuous pressurized aerators include theMorton whisk (Morton Machine Co., Motherwell, Scotland), the Oakescontinuous automatic mixer (E.T. Oakes Corporation, Hauppauge, N.Y.),the Fedco Continuous Mixer (The Peerless Group, Sidney, Ohio), the Mondo(Haas-Mondomix B. V., Netherlands), the Aeros (Aeros IndustrialEquipment Co., Ltd., Guangdong Province, China), and the Preswhip(Hosokawa Micron Group, Osaka, Japan). Continuous mixers may work tohomogenize or aerate slurry to produce highly uniform and stable foamstructures with uniform bubble sizes. The unique design of the highshear rotor/stator mixing head may lead to uniform bubble sizes acrossthe thickness of the initially wet aerated pre-mixture that is used toform the Structure (prior to drying).

Bubble size of the wet aerated mixture assists in achieving uniformityin the ultimate Structure. In one embodiment, the bubble size of the wetaerated mixture is from about 5 to about 100 microns and anotherembodiment, the bubble size is from about 20 microns to about 80microns.

The uniformity of the bubble sizes causes the Structure to haveconsistent densities in the layers of the Structure. In one embodiment,the wet aerated mixture has a density from about 0.15 to about 0.50g/mol., in one embodiment from about 0.20 to about 0.45 g/mol, in oneembodiment from about 0.25 to about 0.40 g/mol, and in anotherembodiment from about 0.27 to about 0.38 g/mol.

D. Dosing

The wet aerated mixture can be dosed in a variety of ways prior todrying. For example, it can be dosed into individual cavities in a moldor as a continuous sheet. In one embodiment, the wet aerated mixture isdosed using a manifold-type device into individual cavities in a mold.Accurate dosing is needed to prevent over- or under-filling of thecavities. Ideally, the top surface will “self-level” and create asmooth, flat surface in the finished Structures; alternatively, scrapingcan be used to create a smooth, flat surface. Dosing can be performedwith commercially available equipment that has been customized todeliver specific shapes and sizes. Suitable equipment can be provided bythe E. T. Oakes Corporation, Hauppauge, N.Y., OKA-Spezialmaschinefabrik,Darmstadt, Germany, and Peerless Food Equipment, Sidney, Ohio. Productis dosed into molds that provide the desired shape and design for thefinished Structure. Molds can be made from a variety of materialsincluding metals, plastics, and composite materials. The use of flexiblemolds can assist with removal of the finished Structure from the moldsafter drying.

E. Drying

Energy is applied to the dosed, wet mixture to heat the foam andevaporate water. This energy can come from a variety of sources such ashot air, infra-red, radiative heat, etc. As the foam heats up, the airbubbles grow and start pressing against one another. This creates apressure in the thin films that separate the air bubbles, causing thesefilms to drain into the plateau border regions of the cellularstructure. The drying rate and premix rheology is controlled to enablethis film drainage, which in turn leads to the formation of an opencelled foam structure during drying. This open celled foam structureprovides good dissolution in the finished dry foam. If the drying rateand film rheology are not properly matched, the resulting structure maybe a closed or partially closed cell foam which does not dissolve well.Drying can be performed using a variety of commercially availableequipment, for example, impingement air dryer manufactured by Lincoln (adivision of Manitowoc Foodservices) and Autobake Ovens and BakingSystems (Sydney, Australia). Drying via this method may result in agradient of open cells pore sizes. The heat applied to the mold mayresult in uneven heating of the substrate, thus a pore gradient, withthe largest pores forming on the side of the foam which is in contactwith the mold. It will be understood that there may be some residualwater remaining in the solid Structure after the drying process, buttypically not more than about 10% by weight.

F. Conditioning

Under some drying conditions, there is an internal moisture gradientwithin the Structures when they exit the dryer. If this gradient is toolarge, and the center of the Structures are too wet, the quality of theStructures can be compromised in the Structure removal step. TheStructures may be held for a period of time at controlled temperatureand humidity conditions to allow the moisture gradient to equilibratewithin the Structures.

G. Removal from Molds

When molds are used in the dosing step, a combination of mold inversionand suction can be used to remove Structures from the molds. Moldinversion is desirable because the porosity of the dried Structures isrelatively high and can allow vacuum to pass through the Structures.

H. Minors Addition

Additional minor ingredients may be added to the Structurespost-drying—in particular temperature sensitive materials such asperfume that might not withstand the drying conditions. These minors areadded in a way that accurately doses the appropriate amount of materialonto each Structure and provides an acceptable appearance on thefinished Structure. Suitable methods include spray coating, roll coatingand other coating technologies.

I. Other Foam Processing Considerations

Structures produced according to the molding process as described hereinmay, in some instances, form large pores towards the exterior surface ofthe Structure. Such Structures have a top and a bottom. The larger poresmay be on one side of the Structure only, and may be only on the portionof the Structure which contacts a mold, when used. U.S. patentapplication Ser. No. 12/361,634, incorporated by reference herein,describes such Structures, as well as optional physical features thatcan be introduced to the foams by use of appropriate molds.

IV. METHODS OF MANUFACTURE—FIBROUS SUBSTRATES

When the Structure is in the form a fibrous web, it can be prepared bythe process comprising the steps of:

-   -   (a) preparing a processing mixture comprising one or more vinyl        acetate-vinyl-alcohol copolymers; one or more surfactants; and        not more than about 60 wt % water; wherein the processing        mixture has: a viscosity at 70° C. of from about 5,000        centipoise to about 150,000 centipoise;    -   (b) fibrillating the processing mixture into fibers by a fluid        film fibrillation process comprising a first pressurized gas        stream directed against a liquid film of the processing mixture        to form the fibers;    -   (c) at least partially drying the fibers of the processing        mixture by a second pressurized gas stream;    -   (d) depositing the partially dry fibers on a surface to form a        web of partially dry fibrous web structures; and    -   (e) drying the partially dry fibrous web structure to a desired        final moisture content.

Optionally, a surface resident coating can be applied to the Structure.The surface resident coating can be applied on the surface of fiberseither when the fibers are in flight to the collector before forming aweb, or after the web has been dried, as explained later in the SurfaceResident Coating section.

A. Preparation of Processing Mixture

The processing mixture is generally prepared by dissolving the vinylacetate-vinyl-alcohol copolymer in the presence of water, surfactant,optional plasticizer and other optional ingredients by heating followedby cooling. This can be accomplished by any suitable heated batchagitation system or via any suitable continuous system involving eithersingle screw or twin screw extrusion or heat exchangers together witheither high shear or static mixing. Any process can be envisioned suchthat the polymer is ultimately dissolved in the presence of water, thesurfactant, the plasticizer, and other optional ingredients includingstep-wise processing via pre-mix portions of any combination ofingredients.

The pre-mixtures of the present invention comprise: at least about 40%solids, in one embodiment at least about 42%, in one embodiment at leastabout 44%, in another embodiment at least about 46%, and in anotherembodiment at least about 50%, by weight of the pre-mixture, beforefiber formation; and have a viscosity of from about 5,000 centipoise toabout 150,000 centipoise, in one embodiment from about 10,000 centipoiseto about 125,000 centipoise, in another embodiment from about 15,000centipoise to about 100,000 centipoise, in another embodiment from about20,000 centipoise to about 75,000 centipoise, and in still anotherembodiment from about 25,000 centipoise to about 60,000 centipoise.

The wt % solids content is the summation of the weight percentages byweight of the total processing mixture of all of the solid, semi-solidand liquid components excluding water and any obviously volatilematerials such as low boiling alcohols. The pre-mixture viscosity valuesare measured using a Brookfield RVDV-1 Prime Viscometer with CPE-41 coneand a shear rate of 1.0 reciprocal seconds for a period of 300 seconds.

B. Forming Fibers from the Processing Mixture

Fibers can be formed from many processes including, but not limited to,meltblowing processes, spunboding processes, bonded carded webprocesses, melt fibrillation and electrospinning and combinationsthereof. The method of making the fibers can include a single stepfibrillation process. Typical single step fibrillation processes usedfor thermoplastic polymers include melt blowing, melt film fibrillation,spun bonding, melt spinning in a typical spin/draw process, andcombinations thereof. In one embodiment, the fibers can be formed inaccordance with the processes described in U.S. Provisional ApplicationNo. 61/982,469, filed Apr. 22, 2014. In one embodiment, the fibers canbe formed in accordance with the processes described in U.S. applicationSer. No. 13/173,639, filed Jun. 30, 2011 by Glenn Jr., et al.

Spunbonded fibers refers to small diameter fibers which are formed byextruding molten thermoplastic material as filaments from a plurality offine, usually circular capillaries of a spinneret with the diameter ofthe extruded filaments then being rapidly reduced as described in U.S.Pat. Nos. 3,692,618, 3,802,817, 3,338,992, 3,341,394, 3,502,763,3,502,538, and 3,542,615.

Meltblown fibers mean fibers formed by extruding a molten thermoplasticmaterial through a plurality of fine, usually circular, die capillariesas molten threads or filaments into converging high velocity gas streamswhich attenuate the filaments of molten thermoplastic material to reducetheir diameter, which may be to microfiber diameter. Thereafter, themeltblown fibers are carried by the high velocity gas stream and aredeposited on a collecting surface to form a web of randomly dispersedmeltblown fibers. Such a process is disclosed in U.S. Pat. No.3,849,241.

Methods to produce fine fibers additionally comprise melt fibrillationand electrospinning Melt fibrillation is a general class of makingfibers defined in that one or more polymers are molten and are extrudedinto many possible configurations (e.g., co-extrusion, homogeneous orbicomponent films or filaments) and then fibrillated or fiberized intofilaments. Meltblowing is one such specific method (as describedherein). Melt film fibrillation is another method that may be used toproduce submicron fibers. A melt film is produced from the melt and thena fluid is used to form fibers from the melt film. Examples of thismethod comprise U.S. Pat. Nos. 6,315,806, 5,183,670, and 4,536,361, toTorobin et al., and U.S. Pat. Nos. 6,382,526, 6,520,425, and 6,695,992,to Reneker et al. and assigned to the University of Akron. The processaccording to Torobin uses one or an array of co-annular nozzles to forma fluid film which is fibrillated by high velocity air flowing insidethis annular film. Other melt film fibrillation methods and systems aredescribed in the U.S. Pat. Nos. 7,666,343 and 7,931,457 to Johnson, etal., U.S. Pat. No. 7,628,941, to Krause et al., and U.S. Pat. No.7,722,347, to Krause, et al., and provide uniform and narrow fiberdistribution, reduced or minimal fiber defects such as unfiberizedpolymer melt (generally called “shots”), fly, and dust, for example.These methods and systems further provide uniform nonwoven webs forabsorbent hygiene articles.

Electrospinning is a commonly used method of producing sub-micronfibers. In this method, typically, a polymer is dissolved in a solventand placed in a chamber sealed at one end with a small opening in anecked down portion at the other end. A high voltage potential is thenapplied between the polymer solution and a collector near the open endof the chamber. The production rates of this process are very slow andfibers are typically produced in small quantities. Another spinningtechnique for producing sub-micron fibers is solution or flash spinningwhich utilizes a solvent.

There is a difference between submicron diameter fibers made withelectro-spinning versus those made with melt-fibrillation, namely thechemical composition. Electro-spun submicron fibers are made ofgenerally soluble polymers of lower molecular weight than the fibersmade by melt-fibrillation. Commercially-viable electro-spinning methodshave been described in U.S. Pat. No. 7,585,437, to Jirsak et al., U.S.Pat. No. 6,713,011 to Chu et al., U.S. Pat. Publ. No. 2008/0237934, toReneker et al, U.S. Pat. Publ. Nos. 2008/0277836 and 2008/0241297, toPark, and U.S. Pat. Publ. No. 2009/0148547, to Petras et al.

In one embodiment, a form of melt film fibrillation process is used.Generally, this process involves providing a thermoplastic polymericmelt, utilizing a pressurized gas stream to impinge on to the polymericmelt to form multiple fine fibers. Suitable melt film fibrillationmethods are described in—for example, U.S. Pat. Nos. 4,536,361,6,315,806, and 5,183,670 to Torobin; U.S. Pat. Nos. 6,382,526,6,520,425, and 6,695,992, to Reneker; U.S. Pat. No. 7,666,343 to Johnsonet al; U.S. Pat. No. 7,628,941, to Krause et al, and U.S. Pat. Publ. No.2009/0295020, to Krause, et al, published on Dec. 3, 2009—all of whichare incorporated herein as reference in their entirety. The melt filmfibrillation methods can utilize different processing conditions.Torobin' s and Reneker's method more specifically includes the steps offeeding the polymer melt into an annular column and forming a film atthe exit of the annular column where a gas jet space is formed. A gascolumn then provides pressures on the inner circumference of the polymerfilm. When the polymer melt film exits the gas jet space, it is blownapart into many small fibers, including nanofibers, due to the expandingcentral gas.

While the melt film fibrillation methods, included as reference above,describe the use of thermoplastic polymer melt, it is surprising andnon-intuitive that a film fibrillation method can be used for makingfibers of the processing mixture fluids. Specifically, as used, a fluidfilm fibrillation process comprises a pressurized gas stream flowingwithin a confined gas passage, comprising an upstream converging wallsurfaces and a downstream diverging wall surfaces into which theprocessing mixture fluid is introduced to provide an extruded processingmixture fluid film on a heated wall surface that is impinged by the gasstream flowing within the gas passage, effective to fibrillate theprocessing mixture fluid film into fibers. “Converging” means that thecross-sectional area decreases in the direction of gas flow; and“diverging” means that the cross-sectional area increases in thedirection of gas flow. In one embodiment, the gas passage comprises afirst, upstream section into which the gas enters from a supply end, atransition region, and a second, downstream section in which the gasflows to an exit end, wherein the transition region fluidly connects thefirst section to the second section, and the gas passage ends at theexit end of the second section. In a particular embodiment, the firstsection of the gas passage has a monotonically decreasingcross-sectional area from the supply end to the transition region, andthe second section of the gas passage has a monotonically increasingcross-sectional area from the transition region to the exit end of thesecond section. At least one flowing processing mixture fluid stream istransmitted through at least one bounded passage which ends in at leastone opening in at least one of the opposing heated walls. The processingmixture fluid is heated sufficiently in transit to make and keep itflowable until introduced into the gas passage. Each processing mixturefluid stream extrudes in the form of a film from each opening. Eachextruded processing mixture fluid film joins with the gas stream and theprocessing mixture fluid film is fibrillated to form fibers exiting fromthe exit end of the second section of the gas passage. For purposesherein, “monotonically decreasing cross-sectional area” means “strictlydecreasing cross-sectional area” from the upper inlet end to the lowerend of the upstream nozzle section, and “monotonically increasingcross-sectional area” means “strictly increasing cross-sectional area”from the upper end to the exit end of the downstream section of thenozzle.

In a particular embodiment, each extruded processing mixture fluid filmjoins with the gas stream in the second section of the gas passage. Theintroduction of the processing mixture fluid in the second section ofthe nozzle system on a heated diverging support wall has been found toespecially facilitate production of high quality fibers and resultingwebs. In a further embodiment, the location where the extrudedprocessing mixture fluid film joins with the gas in the second,downstream section in order to produce the best quality fibers and webdepends on the type of gas, the nozzle geometry, including angles andtransitions, and the pressure of the gas, and can be located in theupper half of the second section such as for low gas pressureconditions, and can be located in the lower, downstream half of thesecond section such as for high gas pressure conditions. In a particularembodiment, only one processing mixture fluid film forms on at least oneof the heated walls, the gas pressure exceeds about 10 psi, and eachprocessing mixture passage opening from which processing mixture filmextrudes is located in a second, downstream half of the second sectionbetween the transition region and the exit end of the second section. Ithas been found that the second half of the downstream second section canprovide an optimal gas velocity region where fluid film fibrillation isaccomplished very efficiently, yielding higher quality fibrous product.

For the purposes of this disclosure, the bounded passages forpressurized gas and processing mixture fluid together will be referredas “nozzle” or “nozzle system”. The nozzle may have bounded passages ina rectangular slot configuration or circular rounded configuration orelongated oval configuration or any configuration that would enableformation of one or more processing mixture fluid film(s) to be impingedby one or more pressurized gas streams. In particular, for a rectangularslot configuration, one or more pressurized gas streams may flow througha bounded rectangular slot passage to impinge on the processing mixturefluid film that forms on a rectangular wall surface to form theprocessing mixture fibers. In such rectangular slot configuration, thebounded passage for one or more processing mixture fluid may be circularrounded, or elongated oval, or rectangular slot, or any other shape.

Various processes and combinations of processes can be used to make thewebs described herein. Fiber bursting, as disclosed in U.S. Pat. No.7,326,663 by Sodemann et al. can be combined with fluid filmfibrillation described herein on two separate beams on a single line.Various aspects of fiber bursting can be incorporated into fluid filmfibrillation, such as producing fibers of different strengths anddiameters to provide a desired combination of properties. Alternatively,aspects of fluid film fibrillation can be included in other fibrillationprocesses to increase the throughput rate by utilizing a fluid filmfibrillation to form fibers. For example, the fluid film fibrillationprocess described herein could be modified to include a Laval nozzle toaid in drawing down the fibers. Drawing down can aid in furtherattenuation of the fibers.

The fibers described herein may also be produced by other spinningmethods that typically yield submicron fibers. Such methods includeelectrospinning, electroblowing, and flash spinning In general,electrospinning employs an electrostatic force to draw a charged liquidpolymeric formulation from a source to a collector. An electrostaticfield is used to accelerate the liquid formulation from the source tothe collector on which the fibers are collected. Suitable andnon-limiting examples of electrospinning methods for making fibers asdescribed herein, have been described in U.S. Pat. No. 7,585,437, toJirsak et al., U.S. Pat. No. 6,713,011 to Chu et al., U.S. Pat. Publ.No. 2008/0237934, to Reneker et al, U.S. Pat. Publ. Nos. 2008/0277836and 2008/0241297, to Park, U.S. Pat. Publ. No. 2009/0148547, to Petraset al, and U.S. Pat. Publ. No. 2006/0264130, to Karles, et al.

The electroblowing method comprises feeding a polymeric solution to aspinning nozzle to which a high voltage is applied while compressed gasis used to envelop the polymer solution in a forwarding gas stream as itexits the nozzle, and collecting the resulting nanofiber web on agrounded suction collector. Suitable and non-limiting examples ofelectroblowing methods, included herein as references in their entirety,comprise U.S. Pat. No. 7,582,247 to Armantrout et al, U.S. Pat. No.7,585,451 to Bryner et al, U.S. Pat. No. 7,618,579 to Kim et al, U.S.Pat. Publ. No. 2006/0097431 to Hovanec, U.S. Pat. Publ. No. 2006/0012084to Armantrout et al, and U.S. Pat. Publ. No. 2005/0073075 to Chu et al.

Another process to make fibers of the described herein is flashspinning, described in U.S. Pat. No. 3,081,519 to Blades and White(non-limiting example). In the flash spinning process, a polymericsolution at a temperature above the boiling point of the solvent and ata pressure at least autogenous is extruded into a medium of lowertemperature and substantially lower pressure. The sudden boiling whichoccurs at this point causes either microcellular structures orfibrillated networks to form. The fibrillated materials tend to beformed when the pressure changes are most severe, or when more dilutesolutions are used. Under these circumstances the vaporizing liquidwithin the extrudate forms bubbles, breaks through confining walls, andcools the extrudate, causing solid polymer to form therefrom. Theresulting multifibrous strand has an internal fine structure ormorphology characterized as a three-dimensional integral plexusconsisting of a multitude of essentially longitudinally extended,interconnecting, random-length, fibrous elements, referred to asfilm-fibrils. These film-fibrils have the form of thin ribbons of athickness, typically, less than 4 micron. Other suitable andnon-limiting examples of the flash spinning process, included herein asreferences in their entirety, comprise U.S. Pat. Nos. 5,977,237 and5,250,237 to Shin et al, U.S. Pat. No. 5,788,993 to Bryner et al, U.S.Pat. No. 6,638,470 to Schweiger, U.S. Pat. No. 4,260,565 to D'Amico etal, and U.S. Pat. No. 7,118,698 to Armantrout et al.

In a particular embodiment, the processing mixture may be spun intosubmicron (diameter less than about 1 micron) or micro-fiber (diameterranging from about 1 micron to about 10 micron) using methods selectedfrom the group of fluid film fibrillation, melt fibrillation,electrospinning, electroblowing, flash spinning, or combinationsthereof.

The above methods, such as fluid film fibrillation, fiber bursting,electrospinning, or electroblowing, produce a significant number ofdissolvable fibers with an average diameter less than about 1 micron, orsub-micron fibers. In an embodiment, the article comprising Structuremay have at least 25% of all the dissolvable fibers with an averagediameter less than about 1 micron, in one embodiment at least 35% of allthe dissolvable fibers with an average diameter less than about 1micron, in another embodiment at least 50% of all the dissolvable fiberswith an average diameter less than about 1 micron, and in yet anotherembodiment at least 75% of all the dissolvable fibers with an averagediameter less than about 1 micron. However, it may be desirable for aparticular Structure produced by the methods of described herein be suchthat the methods are optimized to produce a significant number ofdissolvable fibers with an average diameter less than about 150 micron,in one embodiment less than about 100 micron, in another embodiment lessthan about 10 micron, and yet another embodiment less than about 1micron with a relative standard deviation of less than 100%,alternatively less than 80%, alternatively less than 60%, alternativelyless than 50%, such as in the range of 10% to 50%, for example. Asmentioned earlier in the present disclosure, the significant numbermeans at least 10% of all the dissolvable fibers, in one embodiment atleast 25% of all the dissolvable fibers, in another embodiment at least50% of all the dissolvable fibers, yet another embodiment at least 75%of all the dissolvable fibers.

C. Forming the Fibrous Web Structure

The partially dry or dried to desired moisture content fibers of theprocessing mixture are laid down on a collector to form a web. Thecollector is typically a conveyor belt or a drum. The collector can beporous and vacuum may be applied to provide suction to aid fiber laydown on the collector. The distance from the orifice to the collectordistance, commonly called die-to-collector distance (DCD), can beoptimized for desired web properties. It may be desired to utilize morethan one DCD used in a web, to change the DCD during production, or tohave different beams with different DCDs. It may be desirable to form aweb with different uniformities by changing the DCD. If the DCD is suchthat fibers are not sufficiently dried before depositing on thecollector, the wet or insufficiently dry fibers may coalesce to formblobs or bundles that may not be desirable and would constitute asdefects. Alternatively, it may be desirable for n Structure to have someor all fibers coalesce completely or partially, e.g., to have structuralintegrity. If the DCD is large and such that fibers are sufficientlydried, the fibers may entangle or stick to one another, but notcoalesce, to form bundles or ropes that may not be desirable. Therefore,depending on the desired Structure, the DCD may be set to form fibrousweb with desirable uniformity and sufficient dryness. Alternatively, thewebs of desirable uniformity may be further dried to obtain moisturecontent desired in the Structure.

Additionally, the die-to-collector distance may be altered along withthe vacuum underneath the collector to obtain desired density of theweb. Generally, the shorter DCD and/or higher vacuum provide denser websrelative to the larger DCD. At shorter DCD and/or higher vacuum, thefibers tend to be “forced” together tightly by the fiberizing fluid jetand/or vacuum suction, while at the larger DCD and/or lower vacuum, thefibers stay fluffy and thus lower density. Therefore, depending on thedesired Structure density, it may be desirable to optimize DCD and/orvacuum for uniformity, dryness, and density.

The fibrous webs of the processing mixture may be formed a desired shapeor shapes including, but not limited to (i) depositing the fibrous webto specially designed molds comprising a non-interacting and non-sticksurface including Teflon, metal, HDPE, polycarbonate, neoprene, rubber,LDPE, glass and the like; (ii) depositing the fibrous web into cavitiesimprinted in dry granular starch contained in a shallow tray, otherwiseknown as starch moulding forming technique; and (iii) depositing thefibrous web onto a continuous belt or screen comprising anynon-interacting or non-stick material Teflon, metal, HDPE,polycarbonate, neoprene, rubber, LDPE, glass and the like which may belater stamped, cut, embossed or stored on a roll.

D. The Optional Drying of the Fibrous Web of the Processing Mixture

The optional drying of the formed partially dried fibrous web of theprocessing mixture may be accomplished by any suitable means including,but not limited to (a) multi-stage inline dryers using convection orthrough-air drying; (b) super-heated steam dryers; (c) drying room(s)including rooms with controlled temperature and pressure or atmosphericconditions; (d) ovens including non-convection or convection ovens withcontrolled temperature and optionally humidity; (e) truck/tray dryers,impingement ovens; (f) rotary ovens/dryers; (g) inline roasters; (h)rapid high heat transfer ovens and dryers; (i) dual plenum roasters, and(j) conveyor dryers.

Optional ingredients may be imparted during any of the above describedfour processing steps or even after the drying process. It will beunderstood that there may be some residual water remaining in theStructure after the optional drying process, but typically not more thanabout 10% by weight.

E. The Optional Preparing of the Surface Resident Coating Comprising theActive Agent

The preparation of the surface resident coating comprising the activeagent may include any suitable mechanical, chemical, or otherwise meansto produce a particulate composition comprising the active agent(s)including any optional materials as described herein, or a coating froma fluid.

Optionally, the surface resident coating may comprise a water releasablematrix complex comprising active agent(s). In one embodiment, the waterreleasable matrix complexes comprising active agent(s) are prepared byspray drying wherein the active agent(s) is dispersed or emulsifiedwithin an aqueous composition comprising the dissolved matrix materialunder high shear (with optional emulsifying agents) and spray dried intoa fine powder. The optional emulsifying agents can include gum arabic,specially modified starches, or other tensides as taught in the spraydrying art (See Flavor Encapsulation, edited by Sara J. Risch and GaryA. Reineccius, pages 9, 45-54 (1988), which is incorporated herein byreference). Other known methods of manufacturing the water releasablematrix complexes comprising active agent(s) may include but are notlimited to, fluid bed agglomeration, extrusion, cooling/crystallizationmethods and the use of phase transfer catalysts to promote interfacialpolymerization. Alternatively, the active agent(s) can be adsorbed orabsorbed into or combined with a water releasable matrix material thathas been previously produced via a variety of mechanical mixing means(spray drying, paddle mixers, grinding, milling etc.). In oneembodiment, the water releasable matrix material in either pellet orgranular or other solid-based form (and comprising any minor impuritiesas supplied by the supplier including residual solvents andplasticizers) may be ground or milled into a fine powder in the presenceof the active agent(s) via a variety of mechanical means, for instancein a grinder or hammer mill. Where the article has a particulatecoating, the particle size is known to have a direct effect on thepotential reactive surface area of the active agents and thereby has asubstantial effect on how fast the active agent delivers the intendedbeneficial effect upon dilution with water. In this sense, the activeagents with smaller particle sizes tend to give a faster and shorterlived effect, whereas the active agents with larger particle sizes tendto give a slower and longer lived effect. In one embodiment the surfaceresident coatings may have a particle size from about 1 μm to about 200μm, in another embodiment from about 2 μm to about 100 μm, and in yetanother embodiment from about 3 μm to about 50 μm.

In some embodiments, it is helpful to include inert fillers within thegrinding process, for instance aluminum starch octenylsuccinate underthe trade name DRY-FLO® PC and available from Akzo Nobel, at a levelsufficient to improve the flow properties of the powder and to mitigateinter-particle sticking or agglomeration during powder production orhandling. Other optional excipients or cosmetic actives, as describedherein, can be incorporated during or after the powder preparationprocess, e.g., grinding, milling, blending, spray drying, etc. Theresulting powder may also be blended with other inert powders, either ofinert materials or other powder-active complexes, and including waterabsorbing powders as described herein.

In one embodiment, the active agents may be surface coated withnon-hygroscopic solvents, anhydrous oils, and/or waxes as definedherein. This may include the steps of: (i) coating the water sensitivepowder with the non-hydroscopic solvents, anhydrous oils, and/or waxes;(ii) reduction of the particle size of the active agent particulates,prior to, during, or after a coating is applied, by known mechanicalmeans to a predetermined size or selected distribution of sizes; and(iii) blending the resulting coated particulates with other optionalingredients in particulate form. Alternatively, the coating of thenon-hydroscopic solvents, anhydrous oils and/or waxes may besimultaneously applied to the other optional ingredients, in addition tothe active agents, of the surface resident coating composition and withsubsequent particle size reduction as per the procedure described above.

Where the coating is applied to the substrate as a fluid (such as by asa spray, a gel, or a cream coating), the fluid can be prepared prior toapplication onto the substrate or the fluid ingredients can beseparately applied onto the substrate such as by two or more spray feedsteams spraying separate components of the fluid onto the substrate.

F. The Optional Combining of the Surface Resident Coating Comprising theActive agents with the Structure

Any suitable application method can be used to apply the surfaceresident coating comprising active agent to the article such that itforms a part of the article. For instance, the Structure can have atacky surface by drying the Structure's surface to a specific watercontent before application of powder to facilitate the adherence of thesurface resident coating comprising the active agents to the Structure.In one embodiment, the Structure is dried to a moisture content of fromabout 0.1 wt % to about 25%, in one embodiment from about 3% to about25%, in another embodiment from about 5% to about 20% and in yet anotherembodiment from about 7% to about 15%. Alternatively, a previously driedStructure's surface can be made to reversibly absorb a desired level ofatmospheric moisture prior to application of the powder within acontrolled humidity environment for a specific period of time untilequilibrium is achieved. In one embodiment, the humidity environment iscontrolled from about 20% to about 85% relative humidity; in anotherembodiment, from about 30% to about 75% relative humidity; and in yetanother embodiment, from about 40% to about 60% relative humidity.

In another embodiment, the Structure is placed in a bag, tray, belt, ordrum containing or otherwise exposed to the powder and agitated, rolled,brushed, vibrated or shaken to apply and distribute the powder, eitherin a batch or continuous production manner Other powder applicationmethods may include powder sifters, electrostatic coating, tribocharging, fluidized beds, powder coating guns, corona guns, tumblers,electrostatic fluidized beds, electrostatic magnetic brushes, and/orpowder spray booths. The surface resident coating comprising the activeagent can be applied over portions or entire regions of the Structure'sexterior surface, and can be applied in a manner to adorn, decorate,form a logo, design, etc.

The surface resident coating comprising active agents can be directlyapplied to fibers as they are being formed. The surface resident coatingmay adhere and/or get embedded on the surface of partially or desirablydried fibers. Suitable and non-limiting examples of applying surfaceresident coatings on fibers, included as references herein in theirentirety, comprise U.S. Pat. Nos. 7,291,300 and 7,267,789 to Chhabra andIsele, and U.S. Pat. Nos. 6,494,974 and 6,319,342 to Riddell.

Where the coating is applied to the substrate in a fluid, it ispreferable that if water is present in the fluid that the water is notsufficient to cause the substrate to undesirable dissolve. In preferredembodiments, the active agent(s) to be applied as an adsorbed thincoating is an anhydrous or substantially anhydrous oil. Other non-watersolvents, such as organic solvents which do not cause the substrate todissolve may also be used. Any suitable application method can be usedto apply the active agent(s) in liquid form to the article such that itforms a surface-resident coating that is adsorbed to at least a portionof the solid/air interface of the article as a thin film. For instance,it can be sprayed, spread, dropped, printed, sandwiched betweendifferent articles or different portions of the same article, layered,injected, rolled on, or dipped. The active agent(s) can be applied overportions or entire regions of the article's exterior surface, and can beapplied in a manner to adorn, decorate, form a logo, design, etc.

To obtain the desired fibrous Structure, the methods described hereinmay be combined. In an embodiment, the dissolvable fibers produced fromone or more methods described herein may be mixed homogenously or inlayers to have desired performance for the Structures described herein.Different methods described herein may be optimized to producedissolvable fibers with substantially or otherwise different actives oruse of a particular surfactant, extensional rheology modifier,plasticizer, polymer structurant water soluble polymer, or otheroptional or required ingredients. Still alternatively, different methodsmay be optimized to produce dissolvable fibers with differentdissolution rates and/or different diameter. In a particular embodiment,the submicron dissolvable fibers produced by the fluid film fibrillationmethod may be mixed homogenously or in layers with the dissolvablefibers produced from fiber bursting or electrospinning or electroblowingmethod. In some embodiments, the dissolvable fibrous web structureproduced by one or more methods, or even by the same method, may have amixture of fibers that have substantially or marginally different fiberdiameter distributions, compositions, surface resident coatings,dissolution rates, or combinations thereof. In case of an embodimentwith a mixture of fibers that have significantly different fiberdiameter distributions, the average diameter of fibers from thedifferent fiber diameter distributions may range from about 0.1 micronto about 150 micron.

Homogenous mixture of fibers produced by one or more methods may have aperformance advantage in optimizing, such as slowing or speeding up thedissolution rates for a particular embodiment Structure, e.g., forcontrolled or timed release of actives. The layering of fibers producedby one or more methods may have a performance advantage in varying thedissolution rate during the use of the Structure, for example, certainactives or ingredients of the composition may need to be delivered atdifferent times during the usage of the Structure, such as timed releaseof surfactant and conditioner, or detergent and bleach, or detergent andsoftener, and so forth. Other advantages of mixing dissolvable fibersproduced by the methods described herein may be specific to a particularStructure.

The homogenous mixing of fibers may be achieved during the forming offibrous web structure, such as via use of different nozzles or blocks orbeams of nozzles employing different methods in a simultaneous fashion,for example, nozzles arranged in a staggered configuration intwo-(planar) and/or three dimensions, or simply dissolvable fiberstreams coming in at various angles with fibers depositing onto thecollector. Examples of homogenously mixing fibers using an array ofplurality of fiber-producing nozzles employing fluid film fibrillationprocess are provided by Torobin in U.S. Pat. Nos. 6,183,670 and6,315,806. The layering of fibers may be achieved during the forming ofthe fibrous web structure, such as nozzles of different methods arrangedadjacent to one another or following one another separated by aparticular distance along the machine direction (the direction conveyorbelt is moving) in a continuous manner, for example, nozzles in separateblocks or beams that are arranged in line along the machine direction.Alternatively, the dissolvable fibrous web structures produced bydifferent methods may be combined offline in batches by layering overanother before or after drying to desired moisture content. Whencombined as layers, one or more dissolvable fibrous web structures,produced by one or more methods, may have fibers that are substantiallydifferent in different layers of the dissolvable fibrous webs. Thedifference in fibers may be in substantially or marginally differentdiameter distributions, compositions, surface resident coatings,dissolution rates, porosities, or combinations thereof. For example, thesubstantially different fiber diameter distribution of fibers indifferent layers may have average diameters ranging from about 0.1micron to about 150 micron.

The Structure may comprise one or more dissolvable fibrous webstructures combined (e.g., laminated, layered, sandwiched, embedded, andso forth) with one or more other types of web structures and/orStructures. Suitable and non-limiting examples of Structures that may becombined include U.S. Pat. Publ. No. 2004/0048759 to Ribble et al, U.S.Pat. No. 6,106,849 to Malkan et al, U.S. Pat. Publ. No. 2007/0225388 toCooper et al, U.S. Pat. No. 5,457,895 to Kearney et al, U.S. Pat. Publ.No. 2009/0232873 to Glenn et al, U.S. Pat. No. 7,196,026 and PCT Appl.No. WO2001/47567 to Di Luccio et al, PCT Application No. WO2007/093558to Simon et al, U.S. Pat. App. Publication Nos. 2008/0035174,2008/0269095, 2007/0128256, and 2007/0134304 to Auburn-Sonneville et al,U.S. Pat. App. Publication No. 2006/0159730 to Simon, and U.S. Pat. Nos.5,342,335 and 5,445,785 to Rhim

V. METHODS OF USE

The compositions described herein may be used for cleaning and/ortreating hair, hair follicles, skin, teeth, the oral cavity, fabric andhard surfaces. The method for treating these consumer substrates maycomprise the steps of: a) applying an effective amount of the Structureto the hand, b) wetting the Structure with water to dissolve the solid,c) applying the dissolved material to the target consumer substrate suchas to clean or treat it, and d) rinsing the diluted treatmentcomposition from the consumer substrate. These steps can be repeated asmany times as desired to achieve the desired cleansing and or treatmentbenefit. Alternatively, the Structure can be inserted into a machine(such as a washing machine or dish washer) in a unit dose manner and themachine can perform the dissolution, treating and rinsing steps.

According to yet another embodiment, a method is provided for providinga benefit to hair, hair follicles, skin, teeth, the oral cavity, fabricand hard surfaces, comprising the step of applying a compositionaccording to the first embodiment to these target consumer substrates inneed of regulating.

Described herein is a method for regulating the condition of hair, hairfollicles, skin, teeth, the oral cavity, fabric and hard surfaces,comprising the step of applying one or more compositions describedherein to these target consumer substrates in need of regulation.

The amount of the composition applied, the frequency of application andthe period of use will vary widely depending upon the purpose ofapplication, the level of components of a given composition and thelevel of regulation desired. For example, when the composition isapplied for whole body or hair treatment, effective amounts generallyrange from about 0.5 grams to about 10 grams, in one embodiment fromabout 1.0 grams to about 5 grams, and in another embodiment from about1.5 grams to about 3 grams.

VI. PRODUCT TYPES AND ARTICLES OF COMMERCE

Non-limiting examples of product embodiments that utilize the Structuresinclude hand cleansing substrates, teeth cleaning or treatingsubstrates, oral cavity substrates, hair shampoo or other hair treatmentsubstrates, body cleansing substrates, shaving preparation substrates,fabric care substrates (including, e.g., softening), dish cleaningsubstrates, pet care substrates, personal care substrates containingpharmaceutical or other skin care active, moisturizing substrates,sunscreen substrates, chronic skin benefit agent substrates (e.g.,vitamin-containing substrates, alpha-hydroxy acid-containing substrates,etc.), deodorizing substrates, fragrance-containing substrates, and soforth.

Described herein is an article of commerce comprising one or moreStructures described herein, and a communication directing a consumer todissolve the Structure and apply the dissolved mixture to hair, hairfollicles, skin, teeth, the oral cavity, fabric and hard surfaces toproduce a cleansing effect, a benefit to the target consumer substrate,a rapidly lathering foam, a rapidly rinsing foam, a clean rinsing foam,and combinations thereof. The communication may be printed materialattached directly or indirectly to packaging that contains the Structureor on the Structure itself. Alternatively, the communication may be anelectronic or a broadcast message that is associated with the article ofmanufacture. Alternatively, the communication may describe at least onepossible use, capability, distinguishing feature and/or property of thearticle of manufacture.

VII. TEST METHODS A. Distance to Maximum Force Method

Measured via a Rupture Method on a Texture Analyzer using a TA-57Rcylindrical probe with Texture Exponent 32 Software. The Structureshould have a thickness of between 4 to 7 mm and cut in a circle with adiameter of at least 7 mm for this method; or carefully cut or stackedto be within this overall thickness and diameter range. The porous solidsample is carefully mounted on top of the cylinder with four screwsmounted on top with the top lid affixed in place on top of the sample.There is a hole in the center of the cylinder and its lid which allowsthe probe to pass through and stretch the sample. The sample is measuredwith a pre-test speed of 1 mm per second, a test speed of 2 mm persecond and a post test speed of 3 mm per second over a total distance of30 mm The distance to maximum force is recorded.

B. Hand Dissolution Method

One Structure, with dimensions of approximately 43 mm×43 mm×4-6 mm, isplaced in the palm of the hand while wearing nitrile gloves. 7.5 cm³ offrom about 30° C. to about 35° C. tap water is quickly applied to theproduct via syringe. Using a circular motion, palms of hands are rubbedtogether 2 strokes at a time until dissolution occurs (up to 30strokes). The hand dissolution value is reported as the number ofstrokes it takes for complete dissolution or as 30 strokes as themaximum.

C. Lather Profile: Lather Volume

The Structure provides a lather profile as described hereafter. Thelather volume assessment is performed on 15g/10 inch flat Orientalvirgin hair switches that have been treated with 0.098g of artificialliquid sebum [10-22% olive oil, 18-20% coconut oil, 18-20% oleic acid,5-9% lanolin, 5-9% squalene, 3-6% palmitic acid, 3-6% paraffin oil, 3-6%dodecane, 1-4% stearic acid, 1-4% cholesterol, 1-4% coconut fatty acid,18-20% choleth-24]. The hair switch is rinsed with 9-11 grain, 100° F.water at 1.5 gallons/min for 20 seconds with a shower nozzle. Fortesting the liquid control products, 0.75 cm³ of liquid product areapplied to the center of the switch, the lower portion of hair on theswitch is then rubbed over the product on the hair 10 times in acircular motion, followed by 40 strokes back and forth (a total of 80strokes). Lather speed is recorded as the number of strokes when thefirst lather is obviously generated during the 80 strokes. Lather fromoperator's gloves is transferred to a graduated cylinder with a 3.5 cminside diameter and with total capacities of either 70 ml, 110 ml, or140 ml depending on the total amount of lather generated (heightmodification of standard sized graduated cylinders via a glass shop).Lather from hair is gathered using one downward stroke on the switchwith a tight grip and is also placed into the cylinder. Total lathervolume is recorded in milliliters. Three runs per test sample areperformed and the mean of the three values is calculated. When testingthe Structure, 0.20+/−0.01 grams of product are weighed with the aid ofscissors if required and applied to the switch and then 2 cm³ ofadditional water are added to the product via syringe. The latheringtechnique is then performed as described for liquid products after a 10second waiting time.

As used herein, the terms “substantially non-lathering” and“non-lathering” are used to mean a lather volume of from 0 ml to 20 ml.

D. Open Cell Foam—Cell Wall Thickness/Pore Size

For open cell foam Structures, the Structure has a Cell Wall Thickness.The Cell Wall Thickness is computed from the scanned images via a microcomputed tomography system (μCT80, SN 06071200, Scanco Medical AG) asdescribed herein. The Cell Wall Thickness is determined according to themethod defined for the measurement of Trabecular Thickness using ScancoMedical's Bone Trabecular Morphometry evaluation.

The Cell wall thickness and spacing is calculated as the trabecularthickness and trabecular spacing using the ImageJ program with BoneJplugin. ImageJ is a public domain, Java-based image-processing programdeveloped at the National Institutes of Health and is available fordownload at http://rsb.info.nih.gov/ij. Information on the developmentof BoneJ can be found in the following article: Doube M, Kłosowski M M,Arganda-Carreras I, Cordeliéres F, Dougherty R P, Jackson J, Schmid B,Hutchinson J R, Shefelbine S J. (2010) BoneJ: free and extensible boneimage analysis in ImageJ Bone 47:1076-9. doi:10.1016/j.bone.2010.08.023.

BoneJ is an open source/free software plugin for ImageJ to facilitatecalculations commonly used in trabecular bone analysis. Images obtainedfrom the Scanco μCT50 have a pixel size equal to 0.002 mm. These imagesare subsampled to 0.004 mm sized pixels for easier data handling andprepared as a series of binary images (slices) using the program, AvisoStandard v6.3.1. Once the binary images are created, they are exportedas a series of 2D TIFF images. The images are then loaded into ImageJusing the “Import Image Sequence” function. They are then analyzed usingthe BoneJ “Thickness” measurement option. The resulting data has unitsof pixels and are converted to millimeters by multiplying each data by0.004.

Weighted Radius can be used to measure the pore diameter. The weightedradius is calculated from the three dimensional data from the mCT. ThemCT can be treated as a stack of two dimensional images in the heightdirection. Estimating the change in bubble diameter from slice to sliceis done using the following steps. Each image (or slice) is converted toa binary image by using an appropriate threshold which separates formulamaterial from void space. Each slice is 3.8 microns. The Structure isassigned the bright foreground pixels (value of one) and void space isdark background pixels (value of zero). For each binary slice, theEuclidean distance transform is calculated. The Euclidean distancetransform assigns each dark pixel a new value based on the distance tothe nearest foreground pixel. Most image processing packages, such asMATLAB, offer the Euclidean distance transform as a standard imageprocessing method. The algorithm can be designed to execute veryquickly. The average of the assigned Euclidean distance valuesmultiplied by 3 is used as a surrogate for void bubble diameter andplotted with respect to height (this value is the weighted radius). Thisweighted radius is then multiplied by two to arrive at the porediameter. This method is further described in the article Maurer,Calvin, Rensheng Qi, and Vijay Raghavan, “A Linear Time Algorithm forComputing Exact Euclidean Distance Transforms of Binary Images inArbitrary Dimensions,” IEEE Transactions on Pattern Analysis and MachineIntelligence, Vol. 25, No. 2, February 2003, pp. 265-270.

E. Specific Surface Area

The Specific Surface Area is measured via a gas adsorption technique.Surface Area is a measure of the exposed surface of a solid sample onthe molecular scale. The BET (Brunauer, Emmet, and Teller) theory is themost popular model used to determine the surface area and is based upongas adsorption isotherms. Gas Adsorption uses physical adsorption andcapillary condensation to measure a gas adsorption isotherm. Thetechnique is summarized by the following steps; a sample is placed in asample tube and is heated under vacuum or flowing gas to removecontamination on the surface of the sample. The sample weight isobtained by subtracting the empty sample tube weight from the combinedweight of the degassed sample and the sample tube. The sample tube isthen placed on the analysis port and the analysis is started. The firststep in the analysis process is to evacuate the sample tube, followed bya measurement of the free space volume in the sample tube using heliumgas at liquid nitrogen temperatures. The sample is then evacuated asecond time to remove the helium gas. The instrument then beginscollecting the adsorption isotherm by dosing krypton gas at userspecified intervals until the requested pressure measurements areachieved. Samples may then be analyzed using an ASAP 2420 with kryptongas adsorption. It is recommended that these measurements be conductedby Micromeretics Analytical Services, Inc. (One Micromeritics Dr, Suite200, Norcross, Ga. 30093). More information on this technique isavailable on the Micromeretics Analytical Services web sites(www.particletesting.com or www.micromeritics.com), or published in abook, “Analytical Methods in Fine particle Technology”, by Clyde Orr andPaul Webb.

F. Thickness

The thickness of the Structure is obtained using a micrometer orthickness gage, such as the Mitutoyo Corporation Digital Disk StandMicrometer Model Number IDS-1012E (Mitutoyo Corporation, 965 CorporateBlvd, Aurora, Ill., USA 60504). The micrometer has a 1 in. diameterplaten weighing about 32 grams, which measures thickness at anapplication pressure of about 0.09 psi (6.32 g/cm²).

The thickness of the Structure is measured by raising the platen,placing a section of the sample substrate on the stand beneath theplaten, carefully lowering the platen to contact the sample substrate,releasing the platen, and measuring the thickness of the samplesubstrate in millimeters on the digital readout. The sample substrateshould be fully extended to all edges of the platen to make surethickness is measured at the lowest possible surface pressure, exceptfor the case of more rigid substrates which are not flat. For more rigidsubstrates which are not completely flat, a flat edge of the substrateis measured using only one portion of the platen impinging on the flatportion of the substrate.

G. Basis Weight

The Basis Weight of a Structure is calculated as the weight of theStructure component per area of the component (grams/m²). The area iscalculated as the projected area onto a flat surface perpendicular tothe outer edges of the porous solid. For a flat object, the area is thuscomputed based on the area enclosed within the outer perimeter of thesample. For a spherical object, the area is thus computed based on theaverage diameter as 3.14×(diameter/2)². For a cylindrical object, thearea is thus computed based on the average diameter and average lengthas diameter×length. For an irregularly shaped three dimensional object,the area is computed based on the side with the largest outer dimensionsprojected onto a flat surface oriented perpendicularly to this side.This can be accomplished by carefully tracing the outer dimensions ofthe object onto a piece of graph paper with a pencil and then computingthe area by approximate counting of the squares and multiplying by theknown area of the squares or by taking a picture of the traced area(shaded-in for contrast) including a scale and using image analysistechniques.

H. Dry Density

The dry density of a Structure is determined by the equation: CalculatedDensity=Basis Weight of porous solid/(Porous Solid Thickness×1,000). TheBasis Weight and Thickness of the dissolvable porous solid aredetermined in accordance with the methodologies described herein.

Scanning Electron Microscope (SEM) Imaging:

Representative sections are cut from the sponge with a clean razor bladeand mounted with the cut face up on a standard cryo-SEM stub. Samplesare secured onto the stub with carbon tape and silver paint. Samples areimaged using an Hitachi S-4700 FE-SEM fitted with a Gatan Alto 2500 cryostage. Samples are cooled to −95 dC before imaging in the microscope.Samples are lightly coated with Platinum to reduce charging.Representative images are collected at 2 kV, 20 uA extraction voltage,ultra high resolution mode using the lower secondary electron detector.Long working distances are used to allow the entire sample to be imagedin one frame.

I. Open Cell Foam Structures—Star Volume and Structure Model Index

For open cell foam Structures, to measure the cell interconnectivity viathe Star Volume and the Structure Model Index, disk-like samples,approximately 4 cm in diameter and 3 to 7 mm high, are scanned using amicro computed tomography system (μCT80, SN 06071200, Scanco MedicalAG). Each sample is imaged while sitting flat on the bottom of acylindrical tube. Image acquisition parameters are 45 kVp, 177 μA, 51.2mm field of view, 800 ms integration time, 1000 projections. The numberof slices is adjusted to cover the height of the sample. Thereconstructed data set consisted of a stack of images, each 2048×2048pixels, with an isotropic resolution of 25 μm. For data analysis, avolume of interest is selected to be fully within the sample, avoidingthe surface region. A typical volume of interest is 1028×772×98 voxels.

Structure Model Index (SMI) is measured using Scanco Medical's BoneTrabecular Morphometry evaluation with a threshold of 17. With thisindex the structural appearance of trabecular bone is quantified (see T.Hildebrand, P. Rüegsegger. Quantification of bone microarchitecture withthe structure model index. Comp Meth Biomech Biomed Eng 1997; 1:15-23).The triangulated surface is dilated in normal direction by aninfinitesimal amount, and the new bone surface and volume is calculated.By this, the derivative of the bone surface (dBS/dr) can be determined.The SMI is then represented by the equation:

${S\; M\; I} = {6 \cdot \frac{{BV} \cdot \frac{dBS}{dr}}{{BS}^{2}}}$

SMI relates to the convexity of the structure to a model type. Ideal(flat) plates have an SMI of 0 (no surface change with dilation of theplates), whereas ideal cylindrical rods have an SMI of 3 (linearincrease in surface with dilation of rods). Round spheres have an SMI of4. Concave structure gives negative dBS/dr, resulting in negative SMIvalues. Artificial boundaries at the edge of the volume of interest arenot included in the calculation and thus suppressed.

In addition to the Scanco Medical Analysis, Star Volume measurements aremade. Star Volume is a measure of the “openness” of the void space in atwo phase structure. By choosing a random uniformly distributed set ofpoints in the phase of interest (in this case the phase of interest isthe void space or air), lines can be extended in random directions fromeach of these points. The lines are extended until they touch theforeground phase. The length of each of these lines is then recorded.The random points have a sampling of 10 in each direction (x/y/z) and ateach point 10 random angles are chosen. If the line extends to theborder of the ROI of interest that line is discarded (only accept linesthat actually intersect with the foreground phase). The final equationis based upon the research entitled Star Volume In Bone Research AHistomorphometric Analysis Of Trabecular Bone Structure Using VerticalSections; Vesterby, A.; Anat Rec.; 1993 February; 235(2):325-334.:

${{Star}\mspace{14mu} {Volume}} = {\frac{4}{3}{\pi \cdot \frac{\sum{dist}^{3}}{N}}}$

where “dist” is the individual distances and N is the number of linesexamined

J. Open Cell Foam Structures—Open Cell Content

For open cell foam Structures, the Percent Open Cell Content is measuredvia gas pycnometry. Gas pycnometry is a common analytical technique thatuses a gas displacement method to measure volume accurately. Inertgases, such as helium or nitrogen, are used as the displacement medium.The sample of the Structure is sealed in the instrument compartment ofknown volume, the appropriate inert gas is admitted, and then expandedinto another precision internal volume. The pressure before and afterexpansion is measured and used to compute the sample Structure volume.Dividing this volume into the sample Structure weight gives the gasdisplacement density.

K. Fibrous Structures—Fiber Diameter

For fibrous Structures, the diameter of dissolvable fibers in a sampleof a web is determined by using a Scanning Electron Microscope (SEM) oran Optical Microscope and image analysis software. A magnification of200 to 10,000 times is chosen such that the fibers are suitably enlargedfor measurement. When using the SEM, the samples are sputtered with goldor a palladium compound to avoid electric charging and vibrations of thefibers in the electron beam. A manual procedure for determining thefiber diameters is used from the image (on monitor screen) taken withthe SEM or the optical microscope. Using a mouse and a cursor tool, theedge of a randomly selected fiber is sought and then measured across itswidth (i.e., perpendicular to fiber direction at that point) to theother edge of the fiber. A scaled and calibrated image analysis toolprovides the scaling to get actual reading in microns (μm). Severalfibers are thus randomly selected across the sample of the web using theSEM or the optical microscope. At least two specimens from the web (orweb inside a product) are cut and tested in this manner Altogether atleast 100 such measurements are made and then all data are recorded forstatistic analysis. The recorded data are used to calculate average(mean) of the fiber diameters, standard deviation of the fiberdiameters, and median of the fiber diameters. Another useful statisticis the calculation of the amount of the population of fibers that isbelow a certain upper limit. To determine this statistic, the softwareis programmed to count how many results of the fiber diameters are belowan upper limit and that count (divided by total number of data andmultiplied by 100%) is reported in percent as percent below the upperlimit, such as percent below 1 micron diameter or %-submicron, forexample. We denote the measured diameter (in microns) of an individualcircular fiber as d_(i).

In case the fibers have non-circular cross-sections, the measurement ofthe fiber diameter is determined as and set equal to the hydraulicdiameter which is four times the cross-sectional area of the fiberdivided by the perimeter of the cross of the fiber (outer perimeter incase of hollow fibers). The number-average diameter, alternativelyaverage diameter is calculated as, d_(num)

$\frac{\sum\limits_{i = 1}^{n}\; d_{i}}{n}$

VII. NON-LIMITING EXAMPLES A. Non-limiting Examples of FibrousStructures

Fibers according to the present invention are produced by using asmall-scale apparatus 10, a schematic representation of which is shownin FIGS. 1 and 2. A pressurized tank 12 suitable for batch operations isfilled with a fiber-forming composition 14, for example a fiber-formingcomposition that is suitable for making fibers useful as fabric carecompositions and/or dishwashing compositions.

A pump 16 (for example a Zenith®, type PEP II pump having a capacity of5.0 cubic centimeters per revolution (cc/rev), manufactured by ParkerHannifin Corporation, Zenith Pumps division, of Sanford, N.C., USA) isused to pump the fiber-forming composition 14 to a die 18. Thefiber-forming composition's material flow to a die 18 is controlled byadjusting the number of revolutions per minute (rpm) of the pump 16.Pipes 20 are connected the tank 12, the pump 16, and the die 18 in orderto transport (as represented by the arrows) the fiber-formingcomposition 14 from the tank 12 to the pump 16 and into the die 18. Thedie 18 as shown in FIG. 2 has two or more rows of circular extrusionnozzles 22 spaced from one another at a pitch P of about 1.524millimeters (about 0.060 inches). The nozzles 22 have individual innerdiameters of about 0.305 millimeters (about 0.012 inches) and individualoutside diameters of about 0.813 millimeters (about 0.032 inches). Eachindividual nozzle 22 is encircled by an annular and divergently flaredorifice 24 to supply attenuation air to each individual nozzle 22. Thefiber-forming composition 14 that is extruded through the nozzles 22 issurrounded and attenuated by generally cylindrical, humidified airstreams supplied through the orifices 24 encircling the nozzles 22 toproduce the fibers 26. Attenuation air is provided by heating compressedair from a source by an electrical-resistance heater, for example, aheater manufactured by Chromalox, Division of Emerson Electric, ofPittsburgh, Pa., USA. An appropriate quantity of steam is added to theattenuation air to saturate or nearly saturate the heated air at theconditions in the electrically heated, thermostatically controlleddelivery pipe. Condensate is removed in an electrically heated,thermostatically controlled, separator. The fibers 26 are dried by adrying air stream having a temperature of from about 149° C. (about 300°F.) to about 315° C. (about 600° F.) by an electrical resistance heater(not shown) supplied through drying nozzles (not shown) and dischargedat an angle of about 90° relative to the general orientation of thefibers 26 being spun.

The fibers are collected on a collection device to form a fibrousStructure (nonwoven web) of inter-entangled fibers for example anon-random repeating pattern to a nonwoven web formed as a result ofcollecting the fibers on the belt or fabric.

The process for making fibrous Structures described above is moregenerally set forth in U.S. Provisional Application No. 61/982,469,filed Apr. 22, 2014.

Example 1: Dissolvable Porous Solid Cleanser (Fibrous Structure) withLow Hydrolysis Vinyl Acetate-Vinyl Alcohol Copolymer

Table 1 below sets forth a non-limiting example of a premix (afiber-forming composition) of the present invention for making fibersand/or a fibrous structure (nonwoven web) of the present invention viathe fibrous structure making process described immediately above. Thefibrous Structure is suitable for providing a beauty benefit, forexample suitable for use as a shampoo.

TABLE 1 % by weight of fiber-forming composition Material (i.e., premix)Low Molecular Weight, Low hydrolysis vinyl acetate- 5.13 vinyl alcoholcopolymer¹ High Molecular Weight, Low hydrolysis vinyl acetate- 5.13vinyl alcohol copolymer² Lauryl Hydroxysultaine (40.5% activity) 15.4Sodium Laureth-1 Sulfate (70% activity) 29.9 Cationic cellulose(cationic polymer)³ 0.5 Citric Acid 0.4 Distilled water 43.54 ¹PVA403,Mw 30,000, 78-82% hydrolyzed, available from Kuraray America, Inc.²PVA420H, Mw 75,000, 78-82% hydrolyzed, available from Kuraray America,Inc. ³UCARE ™ Polymer LR-400, available from Amerchol Corporation(Plaquemine, Louisiana)

Into an appropriately sized and cleaned vessel, the distilled water isadded with stirring at 100-150 rpm. The cationic polymer (cationiccellulose) is then slowly added with constant stirring until homogenous.The low hydrolysis vinyl acetate-vinyl alcohol copolymer resin powders(PVA403 and PVA420H) are weighed into a suitable container and slowlyadded to the main mixture in small increments using a spatula whilecontinuing to stir while avoiding the formation of visible lumps. Themixing speed is adjusted to minimize foam formation. Then the mixture isslowly heated to 75° C. for 2 hours after which the Sodium LaurethSulfate and Lauryl Hydroxysultaine are added. The mixture is then heatedto 75° C. while continuing to stir for 45 minutes and then allowed tocool to room temperature to form the premix. This premix is then readyfor spinning into fibers and ultimately making the fibrous structuretherefrom.

Comparative Example A—The following porous solid is not in accordancewith the present invention and is included for comparative purposesonly. Fibers and a fibrous structure are made from the premix describedabove in Table 1 except that the total level of vinyl acetate-vinylalcohol copolymer resin powders (PVA403 and PVA420H) is replaced withthe same total level of high weight average molecular weight (100,000),high hydrolysis polyvinyl alcohol copolymer resin powder (Selvol™Polyvinyl Alcohol 523 (87-89% hydrolyzed) available from SekisuiSpecialty Chemicals).

Into an appropriately sized and cleaned vessel, the distilled water isadded with stirring at 100-150 rpm. The cationic polymer (cationiccellulose) is then slowly added with constant stirring until homogenous.The high weight average molecular weight, high hydrolysis polyvinylalcohol resin powder (Selvol™ Polyvinyl Alcohol 523) is weighed into asuitable container and slowly added to the main mixture in smallincrements using a spatula while continuing to stir while avoiding theformation of visible lumps. The mixing speed is adjusted to minimizefoam formation. Then the mixture is slowly heated to 75° C. for 2 hoursafter which the Sodium Laureth Sulfate and Lauryl Hydroxysultaine areadded. The mixture is then heated to 75° C. while continuing to stir for45 minutes and then allowed to cool to room temperature to form thepremix. This premix is then ready for spinning into fibers andultimately making the fibrous substrate therefrom.

Performance Comparison—For performance testing, the fibrous structuresamples (Example 1 and Comparative Example A) are each cut with scissorsinto 1.25 gram samples on a four place balance and placed ontoindividual plastic weigh boats. Dimethicone with an average viscosity of346,000 cps at 25° C. (CF330M from Momentive Performance Materials,Albany, N.Y.) is applied to each piece at a target level of 0.054 gramson a suitable four place weight balance by brushing onto the surfacewith a small cosmetic brush applicator. If the target weight isexceeded, the excess dimethicone is immediately removed via a smallcosmetic sponge applicator. The samples are stored in bags overnight toenable the applied silicone to spread into the sample prior to testing.The dimethicone level is estimated to be approximately 4.3% by weight ofthe resulting sample (0.054 grams of dimethicone per 1.25 grams ofsample).

The samples are tested according to the Hand Dissolution Methoddescribed herein to determine their dissolution rates. From Table 2below, it is seen that while Example 1 of the present invention (usinglow hydrolysis Vinyl Acetate-Vinyl Alcohol Copolymer) exhibits excellentdissolution, Comparative Example A (using high hydrolysis polyvinylalcohol) does not.

TABLE 2 Comparative Example 1 Example A (# of strokes) (# of strokes)Dissolution Rate 4 >30 (gel blocking, didn't dissolve)

B. Non-limiting Examples of Open Cell Foams Examples 2 and 3:Dissolvable Porous Solid Cleanser (Open Cell Foam) with Low HydrolysisVinyl Acetate-Vinyl Alcohol Copolymer

Table 3 below sets forth non-limiting examples of premixes for making anopen celled foam Structure of the present invention. The premixes areformed using relatively low water (c. 60 wt %)/high solids (c. 40%)solids content. The foam Structure is suitable for providing a beautybenefit, for example suitable for use as a shampoo.

TABLE 3 Example 2 Example 3 Component Wt % Wt % Distilled water qs qsGlycerin 3.8 3.8 Polyvinyl alcohol 420H¹ 9.5 6 Polyvinyl alcohol 205² —3.5 Sodium Laureth-3 sulfate 1.8 1.8 Sodium Laureth-1 sulfate 12.9 12.9Sodium Lauryl Amphoacetate 9.6 9.6 Guar Hydroxypropyltrimonium 0.5 0.5Chloride³ Citric Acid 1.8 1.8 Total 100 100 ¹PVA420H, Mw 75,000, 78-82%hydrolyzed, available from Kuraray America, Inc. ²PVA 205, Mw 39,000,87-89% hydrolyzed, available from Sekisui Specialty Chemicals ³Jaguar ®C500 supplied by Solvay-Rhodia Note that the wt % value for the SodiumLaureth-3 sulfate, Sodium Laureth-1 sulfate and Sodium LaurylAmphoacetate in Table 3 is on final composition basis, i.e., as 100%active.

Into an appropriately sized and cleaned vessel, the distilled water isadded with stirring at 100-150 rpm. The cationic polymer (cationic guar)is then slowly added with constant stirring until homogenous. Thepolyvinyl alcohol resins are weighed into a suitable container andslowly added to the main mixture in small increments using a spatulawhile continuing to stir while avoiding the formation of visible lumps.The mixing speed is adjusted to minimize foam formation. Then themixture is slowly heated to 75° C. for 2 hours after which the SodiumLaureth Sulfates and Sodium Lauryl Amphoacetate are added. The mixtureis then heated to 75° C. while continuing to stir for 45 minutes andthen allowed to cool to room temperature to form the premix.

A foam is prepared from the above liquid processing mixture as describedin Table 4 below via a continuous Oakes aerator and dried within animpingement oven according to the following settings and conditions:

TABLE 4 Premix Mass Flow Rate w/FAM 10″ Die 39.4 g/min Oakes Air FlowMeter Setting 56 Oakes RPM 1941 Wet Density (g/cm³) 0.28 ImpingementOven Temperature (° C.) 132 Drying Time (min) 17.9 Average dry substrateweight (g) 1.1 Average dry substrate density (g/cm³) 0.11 Average basisweight (g/m²) 594

Comparative Example B—The following porous solid is not in accordancewith the present invention and is included for comparative purposesonly. A foam is made from the premix described above in Table 3, exceptno low hydrolysis (less than about 84% alcohol units) vinylacetate-vinyl alcohol copolymer resin powders are included. Instead,only high weight average molecular weight (Mw 100,000), high hydrolysis(87-89% hydrolyzed) polyvinyl alcohol resin powder (Selvol™ PolyvinylAlcohol 523 (87-89% hydrolyzed) available from Sekisui SpecialtyChemicals) is used at 9.5 wt %.

Into an appropriately sized and cleaned vessel, the distilled water isadded with stirring at 100-150 rpm. The cationic polymer (cationic guar)is then slowly added with constant stirring until homogenous. The highweight average molecular weight, high hydrolysis polyvinyl alcohol resinpowder (Selvol™ Polyvinyl Alcohol 523) is weighed into a suitablecontainer and slowly added to the main mixture in small increments usinga spatula while continuing to stir while avoiding the formation ofvisible lumps. The mixing speed is adjusted to minimize foam formation.Then the mixture is slowly heated to 75° C. for 2 hours after which theSodium Laureth Sulfates and Sodium Lauryl Amphoacetate are added. Themixture is then heated to 75° C. while continuing to stir for 45 minutesand then allowed to cool to room temperature to form the premix. Thispremix is then formed into an open cell foam according the sameprocedure described for Examples 2 and 3.

Performance Comparison—For performance testing, the foam samples(Examples 2 and 3 and Comparative Example B) are each cut with scissorsinto 1.25 gram samples on a four place balance and placed ontoindividual plastic weigh boats. Dimethicone with an average viscosity of346,000 cps at 25° C. (CF330M from Momentive Performance Materials,Albany, N.Y.) is applied to each piece at a target level of 0.054 gramson a suitable four place weight balance by brushing onto the surfacewith a small cosmetic brush applicator. If the target weight isexceeded, the excess dimethicone is immediately removed via a smallcosmetic sponge applicator. The samples are stored in bags overnight toenable the applied silicone to spread into the sample prior to testing.The dimethicone level is estimated to be approximately 4.3% by weight ofthe resulting sample (0.054 grams of dimethicone per 1.25 grams ofsample). After application of dimethicone, a 50 gram weight is placed onthe pad for 3 minutes to simulate the impact of compression and otherconditions a packaged foam would encounter after being produced andplaced into commerce.

The samples are tested according to the Hand Dissolution Methoddescribed herein to determine their dissolution rates. From Table 5below, it is seen that while Examples 2 and 3 of the present inventionexhibit good dissolution, Comparative Example B (using only highhydrolysis polyvinyl alcohol) does not. The data for Example 3 alsodemonstrate that high hydrolysis polyvinyl alcohol (e.g., PVA 205) canbe used in a high % solids process to produce useful dissolvable solidStructures, so long as at least one low hydrolysis vinyl acetate-vinylalcohol polymer is also used.

TABLE 5 Comparative Example 2 Example 3 Example B (# of strokes) (# ofstrokes) (# of strokes) Dissolution Rate 8 9 25

Note that any actives and/or compositions disclosed herein can be usedin and/or with the Structure, disclosed in the following U.S PatentApplications, including any publications claiming priority thereto: U.S.61/229,981; U.S. 61/229,986; U.S. 61/229,990; U.S. 61/229,996; U.S.61/230,000; and U.S. 61/230,004.

The dimensions and values disclosed herein are not to be understood asbeing strictly limited to the exact numerical values recited. Instead,unless otherwise specified, each such dimension is intended to mean boththe recited value and a functionally equivalent range surrounding thatvalue. For example, a dimension disclosed as “40 mm” is intended to mean“about 40 mm.”

Every document cited herein, including any cross referenced or relatedpatent or application, is hereby incorporated herein by reference in itsentirety unless expressly excluded or otherwise limited. The citation ofany document is not an admission that it is prior art with respect toany invention disclosed or claimed herein or that it alone, or in anycombination with any other reference or references, teaches, suggests ordiscloses any such invention. Further, to the extent that any meaning ordefinition of a term in this document conflicts with any meaning ordefinition of the same term in a document incorporated by reference, themeaning or definition assigned to that term in this document shallgovern.

While particular embodiments of the present invention have beenillustrated and described, it would be obvious to those skilled in theart that various other changes and modifications can be made withoutdeparting from the spirit and scope of the invention. It is thereforeintended to cover in the appended claims all such changes andmodifications that are within the scope of this invention.

What is claimed is:
 1. A fibrous dissolvable solid structure comprisinga plurality of fibers comprising: from about 3 wt % to about 75 wt % ofa surfactant wherein the surfactant comprises a cationic surfactant; ahigh melting point fatty compound; from about 10 wt % to about 50 wt %of a copolymer comprising vinyl acetate and vinyl alcohol units, whereinthe copolymer comprises not more than about 84% alcohol units and hasweight average molecular weight (Mw) of from about 20,000 to about500,000; wherein the structure has a hand dissolution value of about 1to about 15 strokes and a Distance to Maximum Force value of from about6 mm to about 30 mm
 2. The fibrous dissolvable solid structure of claim1, wherein the copolymer comprises not more than about 82.5% alcoholunits.
 3. The fibrous dissolvable solid structure of claim 2, whereinthe copolymer comprises not more than about 81% alcohol units.
 4. Thefibrous dissolvable solid structure of claim 1, wherein the copolymercomprises from about 65% to about 82.5% alcohol units.
 5. The fibrousdissolvable solid structure of claim 4, wherein the copolymer comprisesfrom about 70% to about 81% alcohol units.
 6. The fibrous dissolvablesolid structure of claim 1, wherein the fibers comprise at least oneadditional copolymer comprising vinyl acetate and vinyl alcohol units,wherein the at least one additional copolymer comprises not more thanabout 84% alcohol units and has a weight average molecular weight offrom about 60,000 to about 300,000.
 7. The fibrous dissolvable solidstructure of claim 1, wherein at least 25% of the fibers have an averagediameter less than about 1 micron.
 8. The fibrous dissolvable solidstructure of claim 7, wherein at least 50% of the fibers have an averagediameter less than about 1 micron.
 9. The fibrous dissolvable solidstructure of claim 1, wherein the copolymer has weight average molecularweight (Mw) of from about 70,000 to about 200,000.
 10. The fibrousdissolvable solid structure of claim 1, wherein the structure furthercomprises a perfume or fragrance.
 11. The fibrous dissolvable solidstructure of claim 1, wherein the structure further comprises aconditioning agent selected from the group consisting of siliconeconditioning agents, cationic conditioning polymers, and combinationsthereof.
 12. The fibrous dissolvable solid structure of claim 1, whereinthe structure comprises from about 5 wt % to about 65 wt % of thecationic surfactant.
 13. The fibrous dissolvable solid structure ofclaim 1, wherein the structure comprises from about 23 wt % to about 75wt % of the cationic surfactant.